An Inside-Out Attempt to Classify Playing Styles

Are Paula Badosa and Emma Navarro actually the same player?

Every so often, an analyst introduces a new way to classify playing styles. The approach usually involves taking a bunch of different stats and identifying clusters of more or less similar players. One group might be aggressive, flat hitters; another might be clay-court experts; a third might be serve-plus-forehand specialists.

Two problems. First, tennis stats tend to be highly correlated. If you’re good at one thing, you’re probably good at most other things. Second, the stats we have aren’t that great. Sometimes we get goodies like spin rate and shot speed from broadcasts, but that’s the exception. Instead, we have to build classifiers from pedestrian metrics like second-serve win rate or–at best–charting-based stats like Backhand Potency and Aggression Score. All of these things are tied to points won, which brings us back to the correlation problem.

I don’t have a solution. I do, however, have a zany idea that might just yield some insights. Instead of classifying players by the most granular metrics we have, what about identifying styles from results?

If two players have the same unexpected head-to-head against, say, Iga Swiatek, they might just have something in common. If both players have similar unexpected head-to-head records against many opponents–not just Iga–it’s probably not just a coincidence, right? We might be able to look at their playing styles and see that they are troubling opponents in similar ways, but even if we didn’t know the first thing about their skills or tactics, we could spot the parallels in their results.

The concept is simple enough. The math is not, and more importantly, the results offer more questions than answers. It’s possible this is a dead end, but I can’t see far enough around the next corner to be sure.

Welcome to the matrix

We’re going to dive into the weeds in a moment. Surely this network graph will entice you to come along?

Those are the 20 most “unique” players in the dataset. The degree of similarity between each pair of players is represented by the thickness of the line that connects them. (I know, you can’t really tell most of the lines apart.) Clara Tauson is a yellow dot because she’s by far the most unique of all.

We’ll come back to that, maybe.

Here’s how this works. I took the 60 players with the most tour-level wins since 2021 and found all the meetings among them. For each pair of players, I used pre-match Elo ratings to determine how “unexpected” the results were, and in which direction. For example, Elo ratings say Jelena Ostapenko usually has a ~20% chance of beating Iga, yet she has done so every time. Ostapenko’s score vs Swiatek, then, is +0.8, and Iga’s score for the same matchup is -0.8. Very few scores are so extreme. Most head-to-heads go roughly as expected, so they hover around zero.

Each player, then, has a score against every other player. Next, I use a method called matrix factorization to analyze and compare those sets of scores. Matrix factorization is commonly used in recommendation systems–if you and I give similar ratings to a bunch of movies and I like a new movie, you’ll probably like it, too. In tennis terms, say that Players A and B have unexpected results against many of the same players. If Player A upsets Aryna Sabalenka, Player B might have a better shot than we think to knock out Sabalenka as well.

In theory, this approach should capture some things about playing style, but it doesn’t actually know anything beyond the Elo-adjusted head-to-heads. Matrix factorization looks for efficient ways to characterize the relationships between players. Those might correspond to real-world attributes like “heavy topspin” or “attackable second serve,” but they might be incomprehensible to us lowly humans.

Mostly incomprehensible

The algorithm decided that the cleanest solution was to divide the 60 players into ten categories. I’ve numbered them, but the order doesn’t matter. Here’s one:

1: Azarenka, Bencic, Kalinskaya, Kasatkina, Kostyuk, Mertens, Parry, Rybakina

    Ok… some flat hitters (except Kasatkina), nobody who likes taking a lot of risk… you can sort of see what’s behind this one. Next:

    2: Alexandrova, Anisimova, Frech, Kontaveit, Muchova, Pegula, Schmiedlova, Vekic

    Flat hitters who swing big, though I wouldn’t have put Pegula in this group. Muchova isn’t a great fit either. Another one:

    3: Begu, Krejcikova, Kvitova, Linette, Maria, Siniakova, Svitolina, Swiatek, Tomljanovic, Vondrousova, Qinwen Zheng

    Ah yes, those noted twinsies, Iga Swiatek and Petra Kvitova. Matrix factorization works in mysterious ways, I guess. Next is my favorite:

    4: Bogdan, Tauson

    Tauson, as noted above, is the most unique player in the dataset. Bogdan is not far behind. That’s the only thing they have in common, right? Onward:

    5: Badosa, Garcia, Haddad Maia, Navarro, Pliskova, Potapova, Sherif

    Almost as head-scratching as the Iga group. Are there any players you’d be less likely to group together than Caroline Garcia and Mayar Sherif? For what it’s worth, the algorithm thinks Badosa and Navarro are the two most similar players in the dataset.

    We don’t need to comment on them all, but here are the rest:

    6: Bouzkova, Kudermetova, Ostapenko, Samsonova

    7: Putintseva, Shnaider, Sorribes Tormo

    8: Blinkova, Bronzetti, Collins, Fernandez, Kalinina, Parrizas Diaz, Sabalenka

    9: Cirstea, Paolini

    10: Cocciaretto, Cornet, Gauff, Gracheva, Jabeur, Keys, Osorio, Sakkari

    If these groupings were based on traditional or charting-based stats, I’d assume there was a coding error. As it is, the clusters do not inspire confidence in this alternative method.

    Style-ish

    Those groups were determined by how players rated on three “style factors” that the algorithm extracted from all those head-to-head scores. Again, we don’t know what they correspond to in the real world, but each one is associated with how players over- and under-perform their ratings.

    This plot shows how players measure up on the first two style factors:

    Ostapenko and Samsonova in one corner, Sorribes Tormo (and Putitnseva, and Bogdan) in the other? This might actually make some sense! From left to right, we have a very approximate ranking of most aggressive to least aggressive, though with curveballs like Marie Bouzkova on the left side (hidden just to the left of Schmiedlova) and Garcia on the right.

    Top to bottom is harder to parse. There’s some correlation between these two style factors, so there’s a whisper of aggression level there. But Paolini on top? I wouldn’t have thought there was any attribute, positive or negative, where she would stand out so much from the crowd.

    Here are scatterplots showing the first and third factors:

    And the second and third:

    I don’t know, man. Iga is hidden in the middle graph because she’s so close to Tatjana Maria. That pretty much says it all.

    A game of matchups

    Here’s the thing–this should work, right? Players have strengths and weaknesses that don’t change too much over time. They are susceptible to certain types of opponents, and they feast on others. People talk like this all the time: It’s why they say tennis is a game of matchups. Coco Gauff struggles against this sort of player, her next opponent is this sort of player. Upset watch!

    It’s possible that my zany idea does work. We could use these clusters and similarity metrics to tweak the Elo prediction for each match and see whether the results improve. Incorporating head-to-heads in pre-match forecasts barely moves the needle, but that’s mostly because there are so few meetings between most pairs of players. Looking at clusters of players increases the sample size, even if there’s a cost in precision. While we might never figure out what these style factors mean, the proof would be in the forecasts. Maybe.

    I don’t have it in me to run that test, at least not this week. Let’s imagine that we did, and that we discovered this was all a worthless exercise. Here are some possible reasons why:

    • Players change too fast. This might be why Paolini is such an outlier: She’s barely the same player she was a few years ago. Any attempt to characterize her will struggle to reconcile 2021-Jasmine with 2024-Jasmine. And she’s hardly the only one to have made noteworthy changes. What’s more, pros are plenty aware of their weaknesses. The type of opponent that bedevils Mirra Andreeva this year might be the focus of an offseason training block.
    • Players are streaky. I suspect that Tauson registers as so unique because she has won and lost in bunches. She reeled off seven in a row in January, but not because she lucked into the right types of opponents. On the flip side, she lost six straight last summer. In both cases, the streak was more about her form than about the styles on the other side of the net.
    • There’s not enough data. In theory, each player’s “profile” is a set of 59 head-to-head scores. But in the last four years, fewer than three-quarters of the possible head-to-heads have been played. Of those, about 40% consist of just one meeting. I’ve given the one-meeting scores less weight, but that’s still a lot of room for noise to take over the profiles.
    • Tennis isn’t really a game of matchups. I’m not willing to go this far, but I do believe that the “game of matchups” business is overstated. For every lopsided Ostapenko-Swiatek head-to-head, there are dozens more boring ones, 2-1 in favor of the better player. The “matchups” line is invoked more often after a match is over, as part of a post-hoc narrative. Betting lines hew far closer to style-neutral Elo ratings than to any kind of matchup/style profile.

    Like I said, more questions than answers. I started this project with ATP data, and believe it or not, the results for men were even more puzzling.

    If you think you know why Sabalenka is grouped with Anna Blinkova and Nuria Parrizas Diaz, the comments are open.

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Monthly Roundup #4: April 2025

    The “Babes”–Evelyn Colyer and Joan Austin–at Wimbledon in the 1920s

    Previous: March

    Lots of tennis this month, and I have an even-more-mixed bag than usual for you:

    1. The Match Charting Project hit a fun milestone a few days ago, as we added our 2,000th unique player, Hanna Chang. She was quickly followed by 1989 Australian Open semi-finalist Jan Gunnarsson. We’re also just a few charts away from 7,000 women’s matches.

    2. Stat of the month has go to Jenson Brooksby, who saved match point in three separate matches en route to the Houston title. Voo de Mar has some context: It was the first time for such a feat in nearly 25 years:

    Runner-up stat of the month might be that Patrick Maloney–ranked 390th when he lost to Brooksby in Houston qualifying–came back a week later and knocked Brooksby out of the first round of the Tallahassee Challenger. As Mike Cation put it: Tennis, man.

    3. Hollywood agent Ari Emanuel, with partners, is buying the Miami and Madrid tournaments from IMG as part of a $1 billion deal.

    I generally don’t care much about who owns which tournaments, but in this case, there could be impact on the tennis itself. Not necessarily positive or negative: IMG likes to give wild cards to its own up-and-coming clients. 16-year-old Moises Kouame was one beneficiary this week, for instance. New owners might favor youngsters, too, but presumably not IMG clients in particular.

    4. Hugh recaps the Barcelona final:

    If we cast our eyes back to the first break point of the match that Alcaraz won, we’ll note that he had to do just that: win it. In other words, Rune wasn’t giving anything in this match. He played the role of counterpuncher perfectly from a deeper court position, yet never abandoned his forecourt instincts when the opportunity arose. Perhaps the rashest shot he hit all day was the forehand return he threaded on set point.

    5. Speaking of Barcelona, did you know it now plays slower than Monte Carlo? I did not. Here are my surface speed ratings from the last 52 weeks:

    (A few tournaments are included twice because their 2024 editions fell less than 365 days before the current one.)

    For many years, Monte Carlo was the most extreme of any event above the 250 level. By my metric, at least, it has now swapped places with Barcelona, which suddenly got slower in 2023. It was never fast, by any means, but 2023-25 is a new era for conditions at the event.

    6. The college tennis season is hotting up, which means it’s time to point you to CollegeTennisRanks. Chris does an impressive job, from upcoming schedules to his mind-bogglingly complex What-If scenarios.

    7. Archive video of the month is courtesy of the USTA, with a 1989 US Open second-rounder between Jimmy Connors and Bryan Shelton:

    If that isn’t enough, there’s also video–thanks again to Voo–of a 1994 final featuring ATP bigwig Andrea Gaudenzi.

    8. Was Ethel Mildred Brooksmith (1865-1944) the early lawn tennis player known as Miss M. Brooksmith? It seems likely.

    9. A few days ago I wrote about the Ostapenko-Swiatek head-to-head. Our new task is to analyze the Ostapenko-Azarenka matchup (5-0 in favor of Vika) for clues, just as Wim Fissette and many other coaches are probably doing.

    If the Vika method doesn’t work, what’s Iga’s next move? Many of you suggested that she needed more variety. Sure, I guess, it doesn’t hurt. But that misses the point. The average rally length in these matches is usually below three shots–there’s no time for variety! If you win all the long rallies, congrats, you’ve won what, six points? The match is decided on serve, serve returns, and some plus-ones. The best you can do is nudge Ostapenko away from cleaning up in those categories.

    Hyper-aggressive game styles are endlessly fascinating to me, in part because they end up influencing everything else. Against Swiatek in Stuttgart, the average rally length was 2.7 shots. Against Sabalenka in the final, it was 2.6. Basically the same, against two such different players! Sabalenka arguably played better defense, even though her scoreline was more lopsided.

    And then, after all this, Ostapenko went to Madrid and lost her first match to the unranked (not unseeded, unranked) Anastasija Sevastova. She’ll have to wreak more havoc another time.

    10. One hundred years ago this month, the British LTA banned photographers:

    The header photo above, of Evelyn Colyer and Joan Austin, shows just how scandalous the dress of the day could be.

    11. Also in April 1925–a century ago today, in fact!–Bill Tilden was a very busy man. He won the singles final at the Greenbrier Country Club in West Virginia, then lost the doubles. In the third set of the mixed final, rain wiped out the remainder, and the match was called a draw.

    As if that wasn’t enough, Tilden began a 500-mile journey to Rye, New York, for an exhibition match the next day.

    Best part of it all is that both venues–the Greenbrier and the Biltmore (now Westchester) Country Club–are still around.

    12. Matt Futterman has a great profile on rising American Ethan Quinn:

    “I thought I was going to come on tour and explode, like Ben Shelton did, or Alex Michelsen,” Quinn, a 21-year-old native of Fresno, Calif. with wavy blond hair and a boyish visage, said during a March interview in Indian Wells. “I thought I was going to take it by storm. That didn’t happen.”

    Nearly two years on from Quinn’s decision, he has evolved into a better tennis player but also into a fable whose ultimate lesson remains unknown.

    Futterman came on my podcast a few years ago. He asked me then what kind of coverage I’d like to see more of in the Times. I’m not sure I gave him a good answer. Now I have a better one: More of this, please!

    12. In the Munich event’s first year as an ATP 500, the field seemed cursed. Several players withdrew the previous week, and five more pulled out after the draw was made. It was so bleak that Christopher O’Connell got in as a lucky loser despite falling in the first round of qualifying.

    I expected to find that the level of the 2025 field was no better than what came before. (There are, certainly, some 250s with fields as strong as Munich’s this year.) But even with the injuries, the first edition as a 500 was a big step up. The median rank of players in this year’s field was 52.5, compared to last year’s 91. This year, 25 of the 32 main-draw entrants ranked in the top 100, 14 of them in the top 50. Last year, only 15 of 28 were in the top 100.

    13. Andre Agassi is headed to the booth:

    TNT Sports has hired eight-time Grand Slam winner Andre Agassi as a studio commentator for the network’s coverage of the French Open this year. Agassi, who won the 1999 French Open and was runner-up three other times, will be a studio analyst during the semifinal and championship rounds at Roland-Garros. In 2024, TNT Sports reached a 10-year, $650M agreement with the French Tennis Federation to add the French Open to its portfolio of premium sports rights in the U.S.

    Always great to see more voices–especially the very best players–do commentary. My impression is that commentary is extremely difficult, and most former players quickly start repeating themselves. I’d rather hear a wide range of perspectives, which means every new voice is welcome.

    14. I enjoyed this rundown of the evolution of Wimbledon qualifying, 1919-1925.

    15. Jannik Sinner is now guaranteed to have 52 weeks at ATP #1:

    This, including a three-month suspension.

    Elo agrees that Sinner remains the best player on tour, even though my algorithm applies a 100-point penalty to players who miss so much time.

    Another way of seeing Sinner’s dominance is to compare the current men’s and women’s lists. No, the lists aren’t meant to be compared, but after decades in which the top women built higher Elo ratings than men–mostly because the level of competition wasn’t as deep–they’ve begun to look similar. For instance, #4 to #10 on the men’s and women’s lists have nearly identical ratings.

    Well, even after the 100-point penalty, Sinner is still 50 points ahead of any other man, and 40 points ahead of Aryna Sabalenka.

    16. More high-quality Challenger streaming! It’s fantastic that all Challenger matches are streamed, but I have a hard time staying interested in the single-camera broadcasts. This will be so much better.

    Also, I continue to be thankful for the Masters events that stream qualifying, as Madrid did this week. Now, WTA, take the hint already!

    17. Speaking of Challenger-level women’s tennis… Raluka Serban won her first-round match in Bogota against Nuria Parrizas Diaz despite committing 22 double faults. She hit 48 second serves and missed nearly half of them. On the bright side, she won 20 of the remaining 26 points.

    My friend Kees, who charted the match and passed along the tidbit, asked if anyone had ever won a match with such a high double-fault percentage. My WTA matchstats data goes back to about 2010, and excluding retirements and lower-level Fed/BJK Cup matches, Serban does crack the top ten:

    Sara Errani, of course, is our champion. Runner-up is the altitude in Bogota.

    18. Even more history for you this month. Fifty years ago this week, Chris Evert waltzed to the Family Circle Cup title:

    The final took so long, Evert said, because her mind was elsewhere. Her on-again, off-again romance with Jimmy Connors was back on, and the pair was engaged. The day that Chrissie faced Martina, Jimbo was in Las Vegas, playing a million-dollar exhibition match against John Newcombe at Caesar’s Palace.

    Connors suffered no such distraction. He shut down Newk in four sets, collecting around half a million dollars–equivalent to about $3MM today–for his efforts.

    19. RIP Pope Francis. Or, as we in the tennis world knew him, the recipient of Juan Martin del Potro’s US Open-winning racket.

    20. This month’s send-off music:

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Why Can’t Iga Swiatek Beat Jelena Ostapenko?

    Jelena Ostapenko in Stuttgart

    Jelena Ostapenko is now 6-0 against Iga Swiatek. Their first meeting doesn’t really count: It was on grass, and Iga was 18. Since then:

    One was close, and Swiatek picked up a set in two others. These are (usually) not blowouts. But most of the time Iga faces an opponent outside the top 20, it is a blowout–in the other direction.

    Ostapenko is a special case. No one on tour is more aggressive. Her make-or-break style, standing inside the baseline and swinging for winners even on service returns, turns every match into something more like a coin flip. If her aim is off, she can lose to anyone. By the same token, she’s the worst opponent for a top seed to draw in the middle rounds:

    Career, Ostapenko has 25 top-ten wins, 21 of them when she was outside the top ten herself. It’s an exaggeration to say that her opponent doesn’t matter, but opponent matters less to the Latvian than to probably anyone else on tour.

    Keep it simple

    It’s tempting to go straight to the mental explanation: Ostapenko has gotten into Iga’s head, etc. That might explain why the head-to-head is 6-0 instead of 4-2 or 5-1. But there is a more concrete basis for the fact that the underdog keeps coming out ahead.

    One of Swiatek’s lesser-known assets is her ability to win serve points. While she doesn’t have the best serve on tour, her opening delivery is quite fast, she rarely misses, and it sets up the rest of her game to finish off points. Over the last 52 weeks, she has held 79% of her service games, more than any other WTA player: Yes, even Aryna Sabalenka.

    In their last five meetings, Ostapenko has broken her 31 times.

    Against everybody else, Iga gets her share of service winners, and when the ball comes back, her unparalleled baseline skills keep the odds in her favor. Though she can rally with the best of them, she keeps points relatively short. Her serve points average 3.8 strokes, compared to tour average of 4.2.

    Against Ostapenko on Saturday, her average serve point lasted 2.8 shots.

    Another way to see the Penko effect is to look at the horrible things she does to Swiatek’s top-line serve numbers:

    Matches   1stIn  1st W%  2nd W%  
Last 52   64.9%   68.3%   50.3%  
vs Penko  57.8%   51.8%   45.7%

    Among the WTA top 50, Iga ranks in the top dozen for all three of those stats. The Latvian turns her into a wholly ineffectual version of herself. (In my earlier piece about Ostapenko, I wrote that she turns the rest of the tour into Madison Brengle. Even Iga!)

    52% of first-serve points won is atrocious. No top-50 player stands below 57%. Sara Sorribes Tormo is the only woman who can compare. 46% isn’t quite so dire: Elise Mertens typically plays at that level, to take one example. But it’s a marked decline from Swiatek’s usual standard.

    If you want to make case that Ostapenko has gotten into Iga’s head, the first-serve-in rate is one place to start. There is some tactical basis for taking more first-serve risks against a free swinger. But in this case, they don’t seem to pay off at all. That dreadful 52% win rate on first serve points is the result of hitting them bigger! Iga took more chances on second serves as well. She is typically one of the stingiest women on tour when it comes to double faults, but she piled up eight of them on Saturday.

    The clay conundrum

    I intended to write a version of this piece back in February, when Ostapenko trounced Swiatek in Doha. Though I missed my chance, I intended to make clear that Iga couldn’t beat her nemesis on hard courts.

    And here we are, two months later. Ostapenko leads the clay-court head-to-head, 1-0.

    Sort of. Stuttgart’s conditions are hardly those of Rome or Roland Garros. The tournament is held indoors, and the surface doesn’t behave like the crushed brick in Paris. Big servers have traditionally done better in Stuttgart than elsewhere on European clay. Ashleigh Barty won the title in 2021, and both Linsday Davenport and Maria Sharapova three-peated. Iga is a two-time champ as well, but not because the surface is particularly favorable.

    Ostapenko scored her latest “upset,” then, on a relatively fast dirt court, one of that doesn’t give Swiatek’s topspin the big bounce it gets on traditional clay. A lower bounce lets the Latvian step in and swing away, much like she does on hard.

    On the other hand, Penko is far from hopeless on the slow dirt. She beat Simona Halep to win the 2017 French Open! Worse, from Iga’s perspective, surface speed doesn’t seem to hinder her game style. Here are the rally lengths from the last few “slow clay” Ostapenko performances logged by the Match Charting Project:

    Match               Result           RallyLen  
2024 Rome           L vs Sabalenka        2.6  
2023 Roland Garros  L vs Stearns          2.7  
2023 Roland Garros  W vs Martincova       3.4  
2023 Rome           L vs Rybakina         2.9

    It’s not the most instructive sample–Ostapenko vs Sabalenka is going to come out under three shots per point on a court made of glue–but it’s clear that the Latvian doesn’t morph into Chris Evert when the conditions change.

    At a certain level of aggression, surface just doesn’t matter that much. While Ostapenko doesn’t have an elite serve, she successfully targets the corners, opening up space for easy (for her) winners on the next shot. She takes such breathtaking risks that opponents sometimes are still leaning the wrong way as her shot finds a corner. Slow clay gives players an extra split second to react and respond. A split second is not enough to negate the Ostapenko barrage.

    What to do?

    Swiatek is one of the best players in the world–indeed, she already ranks among the all-time greats. It can’t really be hopeless.

    There are basically two options: Stop Ostapenko from playing her game, or play Ostapenko’s game, but better.

    In Stuttgart, Iga seemed to attempt the second. As we’ve seen, she took more chances on both first and second serves, though that tactic didn’t work out. She hit service returns harder, aiming for lines rather than relying on her topspin to give her a Nadal-esque margin of safety on groundstrokes.

    At times, it worked. Swiatek hit nearly as many winners as Ostapenko in the second set. When the Latvian lost her way a bit, Iga barely let her win a second-serve point, picking up nearly three out of four. Penko broke her six times, but Swiatek got four of them back.

    The play-like-Penko approach should ultimately stop the bleeding. This was the third time the women reached a deciding set; one of these times, the Latvian’s risk-taking will fail to pay off. Nearly everyone else on tour has picked up a win or two against Ostapenko: If Yulia Putintseva can do it, certainly Swiatek can as well.

    Iga, though, would prefer something more than just continuing to flip the coin. Is there a way to consistently beat someone with such an outrageously dictatorial game style?

    I’d love to give you a galaxy-brain answer here, but I don’t have one. (Wim Fissette hasn’t helped Iga find one either, so I certainly don’t have much of a chance.) At times on Saturday, Swiatek seemed to be trying to wear down the Ostapenko backhand. It is the Latvian’s weaker side, but it is still the source of numerous, often improbable winners. Riskier serving came up empty. The topspin is worthless, though it may have its place in more favorable conditions.

    No one on tour owns Ostapenko the way she owns Iga. (Edit: Except Victoria Azarenka–thanks to several of you for pointing that out.) No style or set of tactics–except Vika’s, so far–stops her every time. Sabalenka had won all three meetings with the Latvian, then she managed just five games in yesterday’s Stuttgart final. Sabalenka is one of the few women who can out-hit anybody, but even that level of power isn’t enough to shut out Ostapenko.

    The only player reliably able to defeat Penko is herself, and even she hasn’t managed it with Iga standing across the net. She may have another chance in just a few days: The two women are lined up to face each other in the Madrid fourth round. Ostapenko is a mere 5-7 at the event in her career, but she is surely salivating at the chance for another shot at her favorite victim.

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Lorenzo Musetti and the One Hand to Rule Them All

    Few backhands are as good as Musetti’s looks

    2024 did not go as planned for Lorenzo Musetti. He started the season having fallen out of the top 20, and he didn’t win back-to-back matches until Miami. The skid continued on clay, where he suffered first-round exits in Estoril, Barcelona, Madrid, and Rome.

    Somehow he found form on grass, reached the Wimbledon semis, then picked up a bronze medal at the Olympics. That was good enough for a return to the top 20, and with last week’s run to the Monte Carlo final, he’s on the cusp of the top ten. Elo already rates him that highly, and even though he is skipping Barcelona this week, he’s likely to rise from 11th to 10th on the ATP computer next Monday.

    Some of the slump could be attributed to distraction: His partner had a baby in the middle of it. (Though that doesn’t explain his decision to play Challengers after losing early in Madrid and Rome.) He’s still just 23, so we could write off the losing streak to the grind of the tour. It takes time to adjust–especially to so much hard-court tennis–and Musetti’s early success might have raised expectations too early.

    The oddest part, though, is the surface mix. Last February, I introduced a stat to measure “surface sensitivity“–how much a player’s results were influenced by surface speed. Not just surface type, but the degree to which a server could dominate. At the time, Musetti was the ultimate slow-court specialist. Guys like Rafael Nadal, Alejandro Davidovich Fokina, and Stefanos Tsitsipas showed strong preferences for the most stately surfaces. But Musetti was more extreme than any of them.

    Then he went near winless on the dirt, and then he went 12-3 on grass. Predictions are hard, especially about the future.

    Yet Musetti’s surface profile is sorting itself out. He excelled at the Paris Olympics, and in the best vindication of my surface sensitivity numbers, he came within a set of scoring his first major title in Monte Carlo. The principality hosts the slowest courts of any major ATP event; it’s no accident that Tsitsipas and Davidovich Fokina have thrived there as well.

    Was 2024 a blip, and is he now Lorenzo, king of the dirtballers? Or is there more to the Italian’s game than slow-court success?

    The one-hander

    Musetti’s signature stroke is his one-handed backhand. He’s now the top-ranked guy with a one-hander, ahead of #16 Tsitsipas and #17 Grigor Dimitrov. Like those two, the Italian is a Federer acolyte.

    Almost by definition, the Musetti backhand is lovely to watch. No winner looks better in a highlight reel than a one-handed backhand winner, and he delivers more than his share. Still, we have to ask: Is it any good?

    The eye test says yes, but the eye test is not trustworthy when it comes to one-handers. Fortunately, the stats agree. My Backhand Potency (BHP) metric, which balances winners (plus forced errors) against unforced errors, as well as shots that precede one or the other, puts Musetti among the top third of ATP regulars:

    The chart shows BHP per 100 backhands for all players with at least 10 charted matches in the last 52 weeks. That includes five guys with one-handed backhands, highlighted in orange. Among those, only Denis Shapovalov is close to the Italian. The other three are in negative territory.

    (You can look up other players on the career list. Federer and Stan Wawrinka are both around neutral. Richard Gasquet stands at +2.0, close to Musetti’s current level.)

    We don’t have BHP for every match, but there are signs that Musetti’s backhand was particularly effective last week. The stat reached +5.5 in both his second-rounder against Jiri Lehecka and the final against Alcaraz. Whatever the limitations of the one-handed backhand in general, the shot isn’t holding the Italian back.

    The best defense…

    Topspin backhands, even pretty ones, are best in moderation. Given a choice, just about everyone this side of Alexander Zverev will hit a forehand instead. It’s particularly important to pick the right spots with a one-hander, as the stroke takes more time to prepare. It is also less forgiving when the timing isn’t perfect.

    While no single formula applies to everyone, the ideal player will run around some backhands in favor of their forehand, and they’ll skip other backhands in favor of more conservative slices. Here’s how Musetti ranks against his peers over the last year–and the career numbers of a few all-time greats–as measured by forehands-per-groundstroke and slices-per-backhand:

    Player              FH/GS  BH Slice%  
Grigor Dimitrov     48.5%      55.4%  
Lorenzo Musetti     50.5%      39.4%  
Stefanos Tsitsipas  52.4%      22.3%  
Mpetshi Perricard   55.1%      32.4%  
Denis Shapovalov    56.8%      32.4%  

Career:                               
Roger Federer       48.8%      37.0%  
Richard Gasquet     45.0%      22.9%  
Stan Wawrinka       49.9%      31.3%

    The Federer number reminds us that FH/GS isn’t about how often a player would prefer to hit a forehand. Everybody targets the backhand, and the worse your backhand, the more they take aim. So Fed’s 48.8% is what results when far more than half of shots were aimed at that side. He slipped around them for as many forehands as he could justify.

    The Italian’s numbers are surprisingly close to both Fed’s and Wawrinka’s. He manages to hit a few more forehands–perhaps because the data we have for him is skewed a bit toward clay–and he slices more than Roger did. That’s a clue as to why Musetti can hold his own on grass: He’s right at home prolonging points with slice backhands.

    Forehand-finding is also a clue as to why Lorenzo’s fortunes are on the uptick. Here’s a selection of his FH/GS rate in recent notable clay-court matches:

    Match                 Result          FH/GS  
2025 Monte Carlo F    L vs Alcaraz    62.0%  
2025 Monte Carlo R32  W vs Lehecka    56.0%  
2024 Olympics BR      W vs FAA        49.2%  
2024 Olympics SF      L vs Djokovic   44.9%  
2024 Olympics QF      W vs Zverev     44.8%  
2024 Umag F           L vs Cerundolo  41.8%

    The Alcaraz match is a tough one to parse, because the stats incorporate Musetti’s attempt to play it out with an injury. But though he lost, he was right there with the Spaniard for the first ten or eleven games. He only needed to hit two plus-one backhands in the entire first set.

    However we handle the Monte Carlo final, it should be clear by now that there’s a big difference between 45% and 55% forehands. At 45%, opponents are trying to exploit that wing and the player is happy to hit backhands, a la Zverev or Daniil Medvedev. The Italian may finally be taking a page from the playbooks of compatriots Matteo Berrettini and Lorenzo Sonego, saving his backhand for when he really needs it.

    Going hard?

    If Musetti is going to make a permanent home in the top ten, he’ll need more hard-court wins. He could get by with an annual romp through clay season, especially if he continues to rack up wins on grass. But the latter seems like a big ask, and there just aren’t enough events on dirt these days for a single-surface guy to find stardom.

    The Italian does have a hard-court title: Naples in 2022, where he beat Berrettini in not-so-fast conditions. He added a final last year on speedy courts in Chengdu; the caveat there is that he didn’t face a single top-40 opponent.

    Bigger picture: Musetti is 3-11 against top-tenners on the surface, and those three wins don’t inspire confidence. He knocked out a passive Zverev in Vienna last year, beat Casper Ruud in Paris, and got past Diego Schwartzman back in 2021. In those 14 matches, he won fewer than 57% of service points. None of the wins were straight-setters, and all of the losses were.

    His game, let’s face it, was made for clay. He’s one of the most passive players on tour. Here are the tour’s least aggressive players–by rally aggression score, a measure of how often the player ends points for good or bad, scaled between -100 and +100–over the last 52 weeks, minimum ten charted matches:

    Player            RallyAgg  
Daniil Medvedev        -93  
T M Etcheverry         -79  
Alex de Minaur         -73  
Lorenzo Musetti        -58  
Sebastian Baez         -53  
Rafael Nadal           -53  
Alexander Zverev       -47  
Gael Monfils           -46  
Novak Djokovic         -46  
Marcos Giron           -45

    Musetti is less aggressive than Zverev. Less aggressive than Sebastian Baez. He hasn’t scored above average on this metric for a single non-grass match in two years.

    In other words: He lets the game come to him, and alas… it does.

    The tour’s most common surface may be the achilles heel of the one-handed backhand. It is of course possible to win on hard with a one-hander, as Federer showed us for the better part of two decades. To grossly oversimplify, he did it by hiding that backhand. Tstisipas’s recent resurgence in Dubai came from maxing out the aggression on that wing.

    You can win on hard courts with passive tennis–go Medvedev!–or you can win on hard courts with a well-shielded one-hander. But it is increasingly clear that you can’t do both. Musetti has proven his potential on both of the game’s natural surfaces, showing off the value of both topspin and slice groundstrokes to do so. That’s enough to make him a top-tenner–barely. To win on hard courts, he will need more Federer-esque tactics to go with his Roger-inspired backhand.

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Lessons From a 48-Shot Rally

    Alexander Zverev lost

    On Tuesday, Matteo Berrettini and Alexander Zverev slugged out a 48-shot rally, the longest of the season so far. It came at 5-5, deuce, in the deciding set. Berrettini won it, opening the door for a final break of serve and a hold to seal the match.

    At almost no stage of the epic point would we have picked the Italian to come out on top. First, it was a Zverev service point. The server’s advantage doesn’t last 48 strokes (or anywhere close), but it gives him an edge for the first several shots. Second, the German is more of a grinder. On reputation, anyway, he’s the easy pick in a marathon rally. Finally, Berrettini thrice found himself digging out of a corner with a defensive chip, a shot that is often an invitation for the man across the net to end the point, even on slow clay.

    Yet long rallies are not well understood. Once the seventh or eighth ball was struck, the odds were only barely in Zverev’s favor. And Berrettini’s chip recoveries, while from defensive positions, didn’t give his opponent much of an advantage.

    It’s easy to picture a strong baseline player outmuscling a weaker one, steadily building up an edge until he is finally able to put the point away, whether on the 8th, 28th, or 48th shot. But while point construction remains a valuable skill, there’s nothing inexorable about it. As we will see, even a mediocre defender can cancel out those efforts and put the rally back on equal footing.

    By the time the stroke count hits double digits, the momentum has probably flipped or reset. By 48 shots, there have been several such shifts. It’s no longer a battle for supremacy but a fight for survival, with an ending that might as well be a coin flip.

    Prolongation

    Virtually everyone on tour wins between 40% and 60% of their double-digit rallies. Based on charted matches from the last 52 weeks, Zverev stands at 51%, with Berrettini at 47%.

    Even in Tuesday’s match itself, the outcome of the marathon point was no outlier. The Italian won 12 of 22 in the ten-plus category. He even won the seven- to nine-shot category by the same margin.

    The players we might think of as long-rally experts have a slightly different skill. They don’t win an overwhelming number of the long points (Casper Ruud: 49%, Lorenzo Musetti: 51%), but they are more likely to get there. Returners begin the point at a disadvantage, so the longer they stick around, the more likely they are to win the point. Zverev doesn’t win many more long rallies than Berrettini does, but he plays a lot more, and those 50/50 propositions are a better deal for him than, say, losing the point six strokes earlier.

    This might sound familiar: I wrote about Daniil Medvedev’s rally-stretching skill about a year ago. Zverev rated as highly as the Russian in terms of dragging points onto equal terms.

    Here is how the returner’s odds look at each stage of the rally, based on clay-court matches since 2020 in the Match Charting Project. The table shows the returner’s win rate when he puts each shot in play:

    Shot #         Point W%  
2 (vs 1st sv)     44.9%  
2 (vs 2nd sv)     52.5%  
4                 52.7%  
6                 54.5%  
8                 55.1%  
10+               56.6%

    Short version: The longer you last, the better your chances. That 56.6% for shot number ten (and beyond) really means something more like 50/50. A pro who has just put the ball in play has a better chance of winning simply because he hasn’t just made an error, and the other guy might. In a very long, evenly-balanced point, the odds will bounce between 60% and 40% in favor of the guy who just landed his last shot.

    Recovery

    If you haven’t seen the rally, jump to 1:22 here:

    (If you have already seen it, go ahead, click, nobody’s gonna know.)

    Zverev’s first real move comes on the 25th shot of the rally (~1:56 in the clip), when he sends a backhand up the line. Berrettini had been cheating to his backhand side, so he’s not ready for it. He’s forced to play a forehand chip to stay alive.

    This is Matteo’s position (at the far end) to hit shot #26:

    Wild guess: If you find every shot that looks like that, you won’t find many guys who come back to win the point.

    Yet Berrettini not only kept the ball in the court, he dropped it within inches of the baseline. The two- or three-shot sequence that Zverev had in mind was now off the table. Maybe the Italian didn’t boost his point-winning odds back up to the standard 56.6%, but he came close.

    It’s no secret that depth matters. I’m going to go one step further and say: However much you think depth matters, it is more important than that.

    Take long-rally shots in general. The Match Charting Project has depth for over 7,000 shots (again, on clay since 2020) that were hit down the middle on the 10th stroke or later. Here is the shotmaker’s chance of winning the point, depending on depth:

    Depth      Point W%  
Shallow       41.3%  
Deep          45.7%  
Very deep     49.4%

    (“Shallow” is anything in front of the service line. “Deep” is behind the service line, but closer to the service line than the baseline. “Very deep” is closer to the baseline.)

    Remember that most players end up between 40% and 60% on long points, and Zverev is barely above neutral. The difference between a shallow groundstroke down the middle and a very deep one is almost as dramatic as the gap between a poor long-rally player (say, Nicolas Jarry) and Zverev.

    Back to the Monte Carlo slugfest: By dropping his forehand near the baseline, Berrettini’s chip recovery almost literally neutralized the point that Zverev had just tilted heavily in his own favor.

    And again

    The German knew he was on to something: He tried essentially the same play two more times in succession. His 31st and 35th shots were both backhands up the line, and an increasingly-gassed Berrettini was leaning the wrong way again. (And again.)

    But twice more, the Italian chipped his way out of trouble. His second hail mary was even better than the first: He not only dropped it very deep, he put it in Zverev’s forehand corner. In other words, he bought himself some time to recover, and he limited his opponent’s ability to keep peppering him wide to the backhand.

    Zverev’s position after Berrettini’s second recovery

    Let’s consider the role of depth for slices, including chips like Berrettini’s. Here is the winning percentage after landing a slice in a long rally, separated by depth and whether the shot was down the middle:

    Depth      Slice-middle W%  Slice-corner W%  
Shallow              34.7%            48.6%  
Deep                 39.3%            43.8%  
Very deep            39.6%            51.8%

    As you’ll see, the very deep, down-the-middle slice isn’t as effective as the typical very deep shot. In the case of Berrettini’s 26th shot, I think his odds were closer to 50% than 40% because it was so deep. But more to the point of his second recovery, on his 32nd shot, the very deep slice to a corner puts him above 50/50.

    Point neutralized, again.

    Endgame

    Ironically, after all of Berrettini’s digs, Zverev the grinder failed to match him. The 46th shot was a strong down-the-line backhand from the Italian. Zverev, accustomed to seeing slices from that wing, lost a split-second of reaction time. He had to chip to stay alive, but his attempt at a neutralizer wasn’t so deep. It barely cleared the service line, right in the middle of the court.

    Matteo, master of the serve-plus-one, puts away balls like these in his sleep:

    Finally in control

    This rally, like most long points, ended up hinging on survival ability. Zverev did a lot of things right, forcing his opponent to play from his weak side, opening up space, attacking that space … and then going at it again when it didn’t work the first time. But on a clay court–especially one as slow as Monte Carlo–the defender always has a chance.

    Or as your youth tennis coach might have said: Just make one more ball.

    The pro equivalent: Yes, make one more ball, and be sure to hit it deep!

    * * *

    Subscribe to the blog to receive each new post by email:

     

    What Do We Make of Sofia Kenin These Days?

    Sofia Kenin in her run to the Tokyo final last year

    Is Sofia Kenin back? Was she ever gone? Was she ever there in the first place? Has any player so persistently defied categorization?

    Big questions aside, Kenin is suddenly more relevant than she has been in at least 18 months. This time last year, she was suffering through a nine-match losing streak. She would add another bad patch in the summer and fall out of the top 150 before reaching last October’s Tokyo final. Since then, she has lost only one first-round match (when she drew Coco Gauff in Melbourne) and made another 500-level final in Charleston. Kenin had set point on Sunday to force Jessica Pegula into a third set before the veteran summoned her mysterious forces and finished the job.

    This is all a far cry from 2020, when the American bracketed the pandemic pause by winning the Australian Open and reaching the French final. But her Charleston showing moves her ranking back up to 34, the highest it has been since late 2023. Her Elo rating is even better, good for 25th on tour.

    What is working again for Sonya? Is she back in the top 40 to stay?

    Oh, those groundstrokes

    When the Kenin game is clicking, it is a joy to watch. She is one of the most versatile players on tour, with the ability and willingness to deploy just about every shot in the book. She tried ten drop shots in the Charleston final against Pegula and sent both forehand and backhand slices across the net. I’ve even seen her win points with moonballs.

    In the 2020s WTA, though, versatility can only be the icing, not the cake. Fortunately for the 26-year-old, both her forehand and backhand are among the game’s best. By my Forehand Potency (FHP) metric, she ranks 16th on tour over the last 52 weeks, in between the fearsome weapons of Iga Swiatek and Amanda Anisimova. Her backhand is the signature shot, and it rates even better, coming in 9th.

    Combined, she gets more value from her groundstrokes than almost anyone else. Here is the top ten, based on charted matches since this time last year:

    Player                 FHP/100  BHP/100  Combined  
Jelena Ostapenko          18.7     11.0      29.7  
Amanda Anisimova           9.2     14.1      23.3  
Aryna Sabalenka           13.0      9.3      22.3  
Ekaterina Alexandrova     13.6      8.5      22.1  
Danielle Collins          12.7      9.0      21.7  
Linda Noskova             14.1      7.4      21.5  
Iga Swiatek               10.0      9.0      19.0  
Madison Keys              11.3      7.5      18.8  
Sofia Kenin                9.4      7.8      17.2  
Jessica Pegula             8.3      8.0      16.3

    For all the heavy hitters on that list, Kenin is more like Pegula than the rest. She attempts to dictate with placement, not power. Give her an opening, and she’ll rarely squander it. She’ll miss as much as some of these sluggers, but that’s because she relentlessly aims for the lines. The overall tally tilts in her favor.

    She falters when she doesn’t have enough space to work with. Pegula, boasting perhaps the best anticipation of anyone on tour, consistently cut down the angles Kenin had to work with on Sunday. Sonya doesn’t have the patience to wait for the next opportunity, so she aimed for narrower and narrower spaces. The result, predictably, was a giant pile of unforced errors. She committed 33 of them off the ground–nearly one in four points.

    Speaking of patience: That’s one category where she resembles the power hitters on that last list. Her average point in the past year has averaged just 3.4 shots, the same as Madison Keys and Ekaterina Alexandrova, fewer than Clara Tauson or Donna Vekic. A bit of a paradox is emerging here: Kenin has an impressive range of all-court and defensive skills, but she doesn’t play like it.

    Is she a… servebot?

    The American doesn’t seem like a weak returner. Aggressive, yes. Too aggressive, maybe. But any woman with such an effective backhand should be able to post decent numbers against the serve.

    Yet: It is a constant struggle to break serve. The typical player in the WTA top 50 breaks 37% of the time. Swiatek grades out at 45.5%, and several more women top 42%. Pegula stands at 38.5%. Kenin, at 30.3%, ranks 48th of 50. Here are her peers at the wrong end of the list:

    Player                Break%  
Lulu Sun               19.7%  
Linda Noskova          28.4%  
Sofia Kenin            30.3%  
Katie Boulter          30.8%  
Clara Tauson           31.2%  
Magda Linette          31.5%  
Xin Yu Wang            32.0%  
Donna Vekic            32.6%  
Ekaterina Alexandrova  32.9%  
Barbora Krejcikova     33.1%

    Judging by some of these names, Kenin might be able to sneak into the top 20 with this return game. Vekic is 20th on the WTA points table. Tauson is 21st.

    If there’s one characteristic that ties many of these players together, it is that their results run hot and cold. Krejcikova has won two slams but often struggled to get past early rounds. Noskova is a nightmare for Iga but manageable for others. Low break rates mean that the margins will always be narrow: Good for upsets and the occasional hot streak, bad for any semblance of consistency.

    Kenin essentially takes the racket out of her own hands. Of players with at least ten matches in the charting database over the last year, only Danielle Collins puts fewer returns in play:

    Player                  RiP%  RiP W%  
Danielle Collins       61.9%   55.7%  
Sofia Kenin            62.5%   54.0%  
Ekaterina Alexandrova  63.2%   58.3%  
Amanda Anisimova       64.3%   58.9%  
Alycia Parks           65.9%   59.6%  
Linda Noskova          66.4%   53.9%  
Liudmila Samsonova     66.9%   56.6%  
Barbora Krejcikova     67.3%   53.9%  
Bianca Andreescu       67.4%   54.4%  
Madison Keys           68.1%   57.6%

    A lot of these names are starting to look familiar. As with the FHP/BHP lists, Kenin shares space with some of the game’s biggest hitters, even if I wouldn’t think of her that way. Maybe she disagrees: She certainly takes chances on return as if she does.

    Yet the results aren’t there. The rightmost column, winning percentage on returns in play, shows that Kenin trails Collins, Alexandrova, Anisimova, and most of the rest by a healthy margin. She is roughly equal to Noskova and Krejcikova, though the Czechs get more balls back to start with. It’s fine to win 54% of points if the denominator is big enough–to take one example of many, Paula Badosa stands at 52%–but Sonya loses too many points without forcing the server to hit even one more ball.

    As for the question in my subhead: No, Kenin isn’t really a servebot. Her serve itself ranks in the middle of the pack. But alas, her return stats are better suited to someone with a much more powerful first strike.

    Same as the old Kenin?

    It is tempting to conclude that Sonya’s 2020 was a remarkable streak of luck. She won the Australian Open after sneaking past Ashleigh Barty in the semi-final, winning fewer than 51% of points. She picked up the Lyon title a month later with four three-setters and five tiebreaks. She reached the Covid Roland Garros final even though Samsonova won more points than she did in their first-round encounter.

    On the other hand, Kenin is a fundamentally different player than she was five years ago. One indicator is her now-languishing break rate:

    Year  Break%  
2018   34.0%  
2019   34.0%  
2020   34.7%  
2021   33.9%  
2022   23.3%  
2023   31.5%  
2024   28.3%  
2025   30.9%

    34% or 35% isn’t great, but it’s worlds apart from where she is now. Rybakina, while off her own peak lately, gets by with just 36%.

    Back then, the American wasn’t so quick to pull the trigger. Based on the 17 matches we have in the charting database, her average point in 2020 lasted 4.1 strokes, another sharp contrast to her 3.4 of the last 52 weeks. 4.1 is at or above tour average, equal to Coco Gauff’s usual mark.

    A big part of the difference is that she put more returns in play. In those 2020 matches, she got 71.7% of serves back, nearly ten percentage points higher than her current rate. She also won more of those points:

    Span      RiP%  RiP W%  
2020     71.7%   55.0%  
Last 52  62.5%   54.0%

    By just about every metric I have, Kenin is more aggressive now than she was at her best, and the strategy isn’t paying off. Perhaps she feels that she has to hit harder–or at least adopt tactics that mimic her more powerful peers–to keep up. Maybe she has lost a bit of quickness: Ankle and foot injuries sidelined her for much of 2022.

    2020-era Sonya, then, is not back. Her form over the last six months suggests she might have landed on something that will work, if not anywhere near her peak level. The stats keep telling us she’s just like Alexandrova, and the risk-taking Russian has spent years in the top 30, picking up a title every year or so and making trouble for her higher-ranked peers. Kenin is on track to do the same.

    Yet unlike Alexandrova, Anisimova, and the rest, Kenin is a former slam champ, with memories of an entirely different level of tennis. Performances like Tokyo and Charleston suggest she is getting closer to recapturing that magic. If she starts getting more serves back, then it’s time for the rest of the tour to worry.

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Trivia Notebook #4: Number Ones, Past and Future

    Would Medvedev now settle for this?

    Previous: Trivia Notebook #3

    Welcome back for some more trivia! Again, thanks to all those who have suggested topics. Feel free to drop them in the comments here, on Twitter, etc.

    Today we’re going to look at Daniil Medvedev’s high ranking sans finals, revisit what would make a good year-end showing for Joao Fonseca, and see who has beaten multiple number ones (past, present, or future) in the same tournament.

    Daniil’s Drought

    Daniil Medvedev hasn’t won a title since 2023; he hasn’t reached a final since Indian Wells in 2024. He won plenty of matches last year–Wimbledon semi, US Open quarter–so when he lost at Indian Wells last month, he was still ranked sixth in the world. He has now fallen out of the top ten, but for a fortnight, he was a top-tenner without a single final in the previous 52 weeks.

    That is unusual:

    Since 1982, the beginning of my reliable week-by-week ATP rankings data, only a few dozen players have held a place in the top 30 without the points from a single final.

    Only nine have clung to a spot in the top 20. (I’m not counting Roger Federer, who remained in the top ten after the Covid-19 pause and held on to a top 20 place for a long time because of the pandemic adjustments to the ranking rules.)

    Medvedev is not the first top-tenner, but his ranking in Miami is the “best” of all-time:

    Rank  Player                 Date  
8     Daniil Medvedev    20250317  
10    Fernando Gonzalez  20100301  
19    Goran Ivanisevic   20020701  
19    Lucas Pouille      20191014  
20    John McEnroe       19921026  
20    Gaston Gaudio      20060731  
20    Andrei Medvedev    20000529  
20    Petr Korda         19990125  
20    Mardy Fish         20120813

    (Each player is listed only once, with their best ranking. Most of them spent multiple weeks in the top 20 without the points from a final.)

    Gonzo had seven semi-finals to his credit, including Rome and Roland Garros. His final-less ranking position is the only one that comes close to what Medvedev has (not) achieved lately.

    Fonseca’s company

    In the first Trivia Notebook, I looked at big ranking leaps into the top 100. The goal was to find some context for Joao Fonseca, who started the year at #145 and had already reached an Elo rating in the top 50. Sure enough, his position on the official table has quickly followed. He’s up to 59th, and he doesn’t have many points to defend for the rest of the year.

    And he’s up to 11th on my Elo list. That’s not a guarantee he’ll climb so high on the ATP table, but it suggests he won’t be 59th for long.

    A one-hundred point leap into the top 50, as it turned out, wouldn’t be all that historic. Eric J followed up to ask:

    How high would he have to get from his starting position for it to be a historically interesting result?

    Let’s say that the reference class for Fonseca consists of players who finished a year ranked between 120 and 180. Again going back to the early 80s, here are the players from that group who reached the best rankings in the following year:

    Player               Year  YE-Rk  Next YE  Gain  
Goran Ivanisevic     2000    129       12   117  
Mikael Pernfors      1985    165       12   153  
Andy Roddick         2000    156       14   142  
Paradorn Srichaphan  2001    120       16   104  
Fernando Gonzalez    2001    139       18   121  
Henrik Holm          1991    131       19   112  
Nicolas Jarry        2022    152       19   133  
Jan Lennard Struff   2022    150       25   125  
Jan Siemerink        1990    135       26   109  
Milan Srejber        1985    121       27    94  
Claudio Mezzadri     1986    138       28   110  
Bohdan Ulihrach      1994    142       28   114  
Dmitry Tursunov      2012    122       29    93  
Francisco Cerundolo  2021    127       30    97  
Tommy Robredo        2000    131       30   101  
Michael Chang        1987    163       30   133

    (“Year” refers to the season with the ranking between 120 and 180: The breakthrough came the following season.)

    No one has ever gone from a ranking in this range to the top ten. Fonseca has a chance to be the first.

    Perhaps more to the point is how the Brazilian would stack up against other teens. Most of the players on that list are young, but the whole notion of “ranking leaps” can distract us from what really matters.

    Fonseca will be 19 at the end of the year. Here are the last ten teenagers to finish a season in the top 20:

    Player           Year  YE Rank  
Carlos Alcaraz   2022        1  
Holger Rune      2022       11  
Novak Djokovic   2006       16  
Andy Murray      2006       17  
Rafael Nadal     2005        2  
Richard Gasquet  2005       16  
Andy Roddick     2001       14  
Lleyton Hewitt   2000        7  
Andrei Medvedev  1993        6

    Pretty good company. Again, there’s a lot to do in the next seven months or so. Elo is a good forecasting tool, but the exact timeline is much tougher to get right. If Fonseca does live up to expectations on schedule, he’ll be in elite company.

    Defeats of past and future

    In the February roundup, I linked to full match video of Andy Murray’s 2005 US Open match against Arnaud Clement. Edo took the cue and charted the match (he’s now past the 1,700 mark!), and he observed that in the same tournament, Clement beat Murray–then a future number one–and former top dog Juan Carlos Ferrero.

    Pretty good run for the 91st-ranked Frenchman, especially in retrospect. Alas, he lost to Nicolas Kiefer in the third round.

    It turns out that a lot of players have beaten multiple (past, present, or future) number ones in the same tournaments. It’s especially common in eras where several men have cycled through the number one position: Not only are number ones comparably weaker, there are more opportunities.

    Let’s strengthen the parameters to make it more interesting. How many players have done the same as Clement, beating a former number one and a present or future number one at the same event, while ranked outside the top 50 himself?

    Clement is one of 25 men to accomplish the feat. But the Frenchman is an even more unique case. He is one of just two players–Slava Dosedel is the other–to have done it twice! A year after his US Open run, he beat Lleyton Hewitt, Marat Safin, and Murray again (also charted by Edo) to win the Washington title.

    Dosedel is the only man to have done this on multiple surfaces. He won the 1996 Munich title with wins over Boris Becker and Carlos Moya on clay. Then he defeated Jim Courier and Pat Rafter at the 1999 Adelaide event, before–get this–losing to Hewitt.

    Clement and Dosedel both came along in the right era for this: 24 of the 27 instances took place between 1995 and 2006. The only example since 2006: the 2018 Australian Open, when Hyeon Chung knocked out both Novak Djokovic and Daniil Medvedev.

    Most impressive of all is a run you’ve surely heard about before. Goran Ivanisevic claimed the 2001 Wimbledon title as a wild card, with wins against former number ones Moya, Rafter, and Safin, plus a victory over future number one Andy Roddick. That single tournament–not to mention Goran himself–continues to be the trivia answer that keeps giving.

    See you next time!

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Jakub Mensik, Tiebreak Wizard

    Probably an ace

    The headline of this piece should end with a question mark. But that seemed churlish, so I saved my skepticism for the next couple thousand words. (Is it a deterrent to warn you of the word count in the first paragraph? Your call!)

    Last week I wrote about the giant-killing game of 19-year-old Jakub Mensik. He kept winning, defeating Jack Draper, Arthur Fils, Taylor Fritz, and Novak Djokovic (among others) to claim the Miami title. His serve numbers boggle the mind. He cracked aces on at least 24% of points in every match before the final. Djokovic held him to a mere 18%.

    While I generally steer clear of the word “clutch,” it was undeniably a clutch performance. The young Czech won all seven tiebreaks he played, including two each against Draper, Fritz, and Djokovic. He allowed Arthur Fils five points in their breaker, but none of the top-tenners managed more than four in a single tiebreak. Awesome as his serving was in general, it was even better at the tail end of those sets.

    Mensik’s tiebreak record is almost as stunning as his ace numbers. Coming into Miami, his career tally at tour level was 23-13, a 64% winning percentage in a category where non-elite players tend to stick around 50%. Djokovic is the all-time leader at 66% (minimum 400 breakers), and only a handful of stars have posted career marks above 60%.

    (I’m excluding tiebreaks from the NextGen Finals event last December. Mensik won just two of eight in Jeddah. The under-21 tourney is played with different rules and doesn’t award ranking points, so it seems logical to leave it out.)

    Having run the table for the last two weeks, the Czech is up to 30-13, a 70% win rate. Mensik sure seems like a young master of the tiebreak. He’s cool under pressure, and he has the monster serve. Is he going to spend the next decade 7-6-ing his peers into oblivion?

    The next 43

    Let’s get some context. Mensik has played 43 tiebreaks, so here are the players (born 1975 or later) with the best records in their own first 43:

    Player                     W-L   Win%  
Pablo Cuevas             33-10  76.7%  
Novak Djokovic           32-11  74.4%  
Marcelo Rios             31-12  72.1%  
Lucas Pouille            30-13  69.8%  
Jakub Mensik             30-13  69.8%  
Sergiy Stakhovsky        29-14  67.4%  
Tommy Haas               29-14  67.4%  
Sebastien Grosjean       28-15  65.1%  
Marcos Baghdatis         28-15  65.1%  
Bernard Tomic            28-15  65.1%  
Milos Raonic             28-15  65.1%  
Botic van de Zandschulp  28-15  65.1%  
Alexei Popyrin           27-16  62.8%  
Kei Nishikori            27-16  62.8%  
Roberto Bautista Agut    27-16  62.8%  
Felix Auger-Aliassime    27-16  62.8%  
Lukas Lacko              27-16  62.8%  
Philipp Petzschner       27-16  62.8%  
Kristof Vliegen          27-16  62.8%  
Dominik Koepfer          27-16  62.8%

    Not bad company, but something of a mixed bag. Mensik is tied for fourth behind an all-time great, a near-Hall of Famer, and a clay court stalwart. The rest of the list includes both top-tenners and journeymen.

    How did these guys fare in their next 43 tiebreaks?

    Player                   First 43  Next 43   Win%  
Pablo Cuevas                33-10    22-21  51.2%  
Novak Djokovic              32-11    33-10  76.7%  
Marcelo Rios                31-12    23-20  53.5%  
Lucas Pouille               30-13    22-21  51.2%  
Jakub Mensik                30-13        -      -  
Sergiy Stakhovsky           29-14    19-24  44.2%  
Tommy Haas                  29-14    20-23  46.5%  
Sebastien Grosjean          28-15    26-17  60.5%  
Marcos Baghdatis            28-15    25-18  58.1%  
Bernard Tomic               28-15    22-21  51.2%  
Milos Raonic                28-15    25-18  58.1%  
Botic van de Zandschulp     28-15    19-23  45.2%  
Alexei Popyrin              27-16    22-21  51.2%  
Kei Nishikori               27-16    25-18  58.1%  
Roberto Bautista Agut       27-16    25-18  58.1%  
Felix Auger-Aliassime       27-16    26-17  60.5%  
Lukas Lacko                 27-16    19-24  44.2%  
Philipp Petzschner          27-16    21-22  48.8%  
Kristof Vliegen             27-16    19-21  47.5%  
Dominik Koepfer             27-16     9-14  39.1%  
TOTAL                     570-290  422-371  53.2%

    (Some of them didn’t make it, or haven’t yet made it, through another 43.)

    These numbers are… less impressive. Djokovic was unstoppable in the early going; he has managed to win “only” 61% after that second batch of 43. Grosjean and Auger-Aliassime came close to matching their first 43s. But the rest of the group made a beeline for mediocrity. Even counting the three standouts, the group won only 53% of their follow-up tiebreaks. 53% is fine–it worked for Marin Cilic and Marat Safin–but if Mensik had won 53% of his career tiebreaks so far, we’d be celebrating a different champion in South Florida.

    Breakcasting

    Bigger picture, there is almost no correlation between a player’s record in their first 43 tiebreaks and their next 43, or their ensuing career.

    Djokovic maintained his breathtaking record because he was extremely good at tennis, not because he had secret tiebreak mojo. Players who aren’t on the way to double-digit slams (and even some who are!) can’t count on winning two-thirds of their tiebreaks.

    This doesn’t mean, however, that everybody trends toward 50% on the dot. Better-than-average pros win more points, both in and out of busters. I introduced a stat a few years ago called Tiebreaks Over Expectation (TBOE), which hinges on that notion of “expectation.” Take a player’s rate of serve and return points won in a given match, plug it into a tiebreak simulator, and you get the likelihood that he’ll be first to seven. No clutch, no wizardry, just the assumption that playes are about the same in breakers as they are the rest of the time.

    Mensik’s idol Tomas Berdych is a good example. He won 225 of his 374 career breakers, a 54% success rate. While it’s a pedestrian number compared to Mensik’s, it’s solid! And it’s precisely what the formula expects. Run the exercise for each of the 374 breakers, and it predicts 225 wins. (224.86, in fact.) In other words, Berdych was exactly as good in the jeu decisif as he was in those matches as a whole.

    TBOE makes for a better–if considerably less exciting–forecast of future tiebreak results. Here’s the top 20 again, with “expected” records for their first 43:

    Player                   Actual  Expected  
Pablo Cuevas              33-10     24-19  
Novak Djokovic            32-11     23-20  
Marcelo Rios              31-12     24-19  
Jakub Mensik              30-13     22-21  
Lucas Pouille             30-13     21-22  
Tommy Haas                29-14     22-21  
Sergiy Stakhovsky         29-14     21-22  
Milos Raonic              28-15     24-19  
Marcos Baghdatis          28-15     23-20  
Bernard Tomic             28-15     22-21  
Sebastien Grosjean        28-15     22-21  
Botic Van De Zandschulp   28-15     22-21  
Kei Nishikori             27-16     24-19  
Felix Auger Aliassime     27-16     23-20  
Kristof Vliegen           27-16     22-21  
Philipp Petzschner        27-16     22-21  
Alexei Popyrin            27-16     21-22  
Roberto Bautista Agut     27-16     21-22  
Dominik Koepfer           27-16     20-23  
Lukas Lacko               27-16     20-23

    An enormous amount of those all-time-best career starts come down to luck. Cuevas really did win those 33 tiebreaks. But his performance in those matches didn’t merit so many 7-6’s in his favor. Fortune caught up with him, and he won less than half of the 170 breakers he played over the remainder of his career.

    Mensik is no exception. Here are his serve and return win rates against his opponents in Miami, along with the resulting probability that he would win a tiebreak in each match:

    Opponent    SPW    RPW  p(TB Win)  
Draper    75.0%  33.7%      65.1%  
Fils      73.6%  42.0%      74.7%  
Fritz     74.3%  30.7%      58.9%  
Djokovic  69.2%  29.7%      48.2%

    Replay the tournament, and some of those seven breakers will almost certainly not go the same way, no matter how calm the Czech is under pressure. The odds of converting all seven tiebreaks against this competition is about 2.5%.

    Yeah, but!

    None of this is meant to take away from what Mensik has accomplished. He is 8-5 against top-tenners. He just won a Masters 1000. He powered through the last fortnight with one unhittable serve after another, especially when it mattered.

    What the numbers do say is that he’s unlikely to keep it up.

    Some of you, surely, want to argue that the 19-year-old will defy the odds. He has a huge serve, and big servers do better in tiebreaks, right? He’s clutch, and that doesn’t just go away–it isn’t like we’re rolling dice to get the outcomes of these tiebreaks.

    These arguments are appealing, in part because we’ve heard them from players and commentators ever since Jimmy Van Alen figured out a slick new way to end sets. But they are not true.

    There’s almost no relationship between a player’s serving ability and his performance in tiebreaks. Of course, the better the serve, the stronger the player, and the better the results, whether we’re talking games or sets or breakers. But when it comes to winning more tiebreaks than expected–getting from Mensik’s expected 22 of 43 to his actual 30 of 43–serving big doesn’t help. (There’s one twist to that rule, and I’ll get there in a minute.)

    Next: If clutch ability exists, it is remarkably fickle. Players do clutch things, like reel off seven tiebreaks against higher-ranked players on a big stage. But that doesn’t mean they’ll be clutch the following week, month, or season. We saw that in the “first 43” versus “next 43” comparisons. Every one of those players with a hot start looked clutch. With the exception of Djokovic and maybe a couple of others, their ability to raise their game in tiebreaks disappeared. Even Novak steadily drifted back to earth.

    Big Jake and Big John

    There are a few big servers who have outperformed tiebreak expectations. The poster boy is John Isner. By my TBOE metric, he won 16% more tiebreaks than he “should” have, flipping the result of about 70 breakers over the course of his career. No one with at least 150 career tiebreaks has consistently stepped up their game so much.

    We can learn a lot from that one example. The main thing is that +16% is the best anyone can reasonably hope for. What if Mensik really is the chosen one of the tiebreak? We’ve already seen a chosen one of the tiebreak, and we know how much his magical skills impacted his results.

    In his first 43 tiebreaks, Mensik has beaten expectations by 36%, more than double Isner’s career mark. If we assume all of the Czech’s superb tiebreak performance is a mirage, we’d expect him to go 22-21. If we grant him an Isnerian level of clutch performance, he moves up to 25-18, or maybe 26-17. At that rate, he’d be climbing the ranking table, but this week’s storyline would be Djokovic and his 100th career title instead of the teen sensation.

    Even +16% is a big ask. Next on the career overperformance list is Nick Kyrgios, at a slightly lower +16%. (I promise it’s not all big servers, and plenty of big servers underperform as well. Ivo Karlovic, Hubert Hurkacz, and Sam Querrey are a few counterexamples.) One thing we know about Kyrgios is that he–sometimes quite blatantly–saves his energy for key points. When he does that, of course he’s going to get better results on the key points, including tiebreaks.

    Did Isner do the same? Maybe not as demonstratively, but I can’t imagine he tried very hard when returning at 30-0 or 40-0. Some of the 16% overperformance can likely to be attributed to that. He played better in breakers because he cared more about every point. It’s a sound tactic for a certain type of player; it’s just not as common among those with more modest serves.

    Mensik, to his credit, is not so one-dimensional. I don’t get the sense he’s conserving energy for tiebreaks, tanking return games, or anything like that. If that’s true, his overall serve and return stats are a good indicator of his true ability level, unlike Kyrgios’s, which are deflated by his occasional apathy. Accurate serve and return stats make it even less likely that Mensik, or anyone else, can improve on them so much at the end of sets.

    The sustain

    There’s another reason why Isner–and Mensik–might outperform expectations. It’s not that they get better in tiebreaks, it’s that their serves are so good that they don’t get worse.

    I looked at tiebreak tactics a few years ago and discovered that servers, on average, become more conservative. Rallies stretch out. Here were the key findings:

    If every player reacted to the pressure in the same way, this would be bad news for someone like Mensik. The longer the rally, the worse he fares. But at least through his first 43 tiebreaks, he has defied the trend. While I don’t have tiebreaks split out for every match, the records I do have suggest he’s winning a whopping 78% of service points in breakers, compared to 65% overall.

    His performances in Miami might have been even better. Facing Djokovic in the final, fewer than half of his serves came back. Against Draper, he served ten points in the two tiebreaks. Only two serves came back.

    I don’t think it’s realistic to expect Mensik to continue to be the greatest server in the history of the sport every time the score reaches six-all. On the other hand, the best servers have more options than their less-fortunate peers. Roger Federer is another guy who outperformed tiebreak expectations. He, like Isner, could hit a first serve at 90% strength that still left returners flat-footed. Mensik may be in the same category. He can pile up aces without taking on an unacceptable amount of risk.

    It’s reigning Mensik

    The Miami title moved the Czech up to 24th in the ATP rankings. My Elo ratings–which don’t make any adjustment for whether tiebreak records are sustainable–put him in 13th place.

    Assuming he comes back to earth and loses closer to half of his tiebreaks, can he sustain that?

    The answer just might be yes–at least for the ATP ranking. Over the last 52 weeks, Mensik has won 50.5% of his points. Here are the ATP top-50 guys who also have total-points won rates in the same range:

    Rank  Player                 TPW  
14    Ben Shelton          50.9%
49    Jan Lennard Struff   50.9%  
25    Sebastian Korda      50.8%  
50    Zizou Bergs          50.7%  
21    Tomas Machac         50.7%  
17    Frances Tiafoe       50.6%  
29    Jiri Lehecka         50.6%  
44    TM Etcheverry        50.5%  
12    Holger Rune          50.5%  
24    Jakub Mensik         50.5%  
34    Alex Michelsen       50.4%  
42    Gael Monfils         50.3%  
48    Miomir Kecmanovic    50.3%  
43    Nuno Borges          50.3%  
40    A Davidovich Fokina  50.2%

    The Czech is basically tied with top-20 players Holger Rune and Frances Tiafoe, and he isn’t far behind another in Ben Shelton. Also of note, John Isner finished 2018 in the top ten with a TPW% of just 51.1%.

    If anything, that comparison understates Mensik’s level. Thanks to his knack for upsetting seeds and going deep in draws, the 19-year-old has faced tougher competition than almost anyone else. Here are the top-50 players who have played the most difficult schedules, as measured by median opponent rank:

    Rk  Player            MdOppRk  
1   Jannik Sinner        27.0  
3   Carlos Alcaraz       28.0  
7   Jack Draper          30.0  
4   Taylor Fritz         30.5  
5   Novak Djokovic       35.0  
24  Jakub Mensik         35.5  
42  Gael Monfils         36.0  
11  Daniil Medvedev      36.0  
2   Alexander Zverev     37.0  
28  Alexei Popyrin       38.0

    Mensik isn’t just winning points at a solid rate, he’s doing so against top-tier competition. Alexander Zverev, Casper Ruud, and Stefanos Tsitsipas have all faced weaker average opponents than the Czech has.

    One takeaway here is that ATP rankings are awfully noisy. They are so dependent on context that it’s virtually impossible to say what a player’s ranking “should” be. Had Mensik’s tiebreak streak ended in the Draper match, he’d still be about the same player, but his ranking would be 20 places lower. In that plausible counterfactual, he’d be underrated.

    As it is, the 19-year-old doesn’t need a 30-13 tiebreak record to be seen as an outstanding player on the rise. He’s a credible top-30 player–maybe more–even without it. Which is good, because he’s not going to keep winning 70% of his breakers. Isner earned his one year-end top-ten finish with a season tiebreak record of just 53%. With a better second serve, Mensik can do the same.

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Monthly Roundup #3: March 2025

    The “under-the-hill gang,” pictured in the March 1975 issue of Oui magazine.

    Previous: February

    Off we go…

    1. One of the Miami quarter-finals pitted two guys who I have recently highlighted as having weak still-developing second serves, Arthur Fils and Jakub Mensik. Mensik advanced, yet neither one showed much progress in that problematic category:

    For Mensik, 50% isn’t bad.

    2. Electronic Line Calling (ELC) is here, and it is quickly spreading to the lower levels of tennis. Colette updates us on the status of ELC in college tennis, where players previously called their own lines.

    3. Roberto made a nice graphic of the longest non-retirement streaks in WTA history:

    There’s a men’s version, too.

    4. RIP Yola Ramirez, the greatest Mexican tennis player in history. She was twice a French Open finalist and picked up two doubles major crowns.

    My records, which are not 100% complete, give her a career singles record of 376-144, spanning the era from 1951 to 1972. She amassed at least 51 career titles, almost all on clay. In five of them, she defeated women who made my Tennis 128 list: Maria Bueno, Darlene Hard, Ann Jones, and Nancy Richey.

    5. The PTPA filed a lawsuit against various tennis bodies, and it raised the usual crop of questions and takes about tennis finances. I appreciate Pete Bodo for framing at least part of it so clearly:

    Tennis has sometimes tried to manage the number of players considered to be pros, for instance by limiting the number of tournaments/round that grant ranking points. But as Pete hints, that isn’t the issue. If there’s a pot of gold for top players, there will be an endless supply of aspirants, whether those aspirants are globetrotting juniors, college players, ITF warriors, or Challenger tour regulars. Enough people out there have federation or family support that they can chase their dreams without earning anything like a living wage (or in some cases, anything at all).

    In practice, the answer is “the number of players who make grand slam qualifying cuts.” But even that is too vague, because players don’t necessarily stay at that threshold for long. All this is to say: People who lobby for a different financial structure should start with these questions. How many players should earn a living wage from tennis? And then, what changes would be necessary to make that happen?

    5. Patrick Ding writes about women’s tennis like no one else does, often covering players you haven’t heard of. Here he is on the scheduling decisions of Tereza Valentova.

    6. There’s a tennis element in the new BBC series, Towards Zero, based on an Agatha Christie novel. Simon Briggs looks into the true story behind the fiction:

    On the tennis court, Strange and Goold were each renowned for their “killer” backhands – a detail which becomes a key plot point in the book. And if Christie has transposed the drama from the French Riviera to the English one, that is probably because of her own upbringing in Torquay.

    7. Ben Marrow built a tennis twist on a basketball dataviz I included in last month’s roundup:

    He also made a slick interactive version.

    8. If you’re not reading Andrea Petkovic, well … maybe this, about Monica Niculescu will finally get you started?

    She was an immensely talented player who did everything she could to mess with your technique and I’m not afraid to admit that it worked. I got my revenge once we were older and I was taller and stronger and didn’t have a complete meltdown every time she hit a slice. But the panic reared its ugly head until the very end of my tennis player’s days whenever I saw Moni Niculescu near me in the draw. Some things fade, some things are forgotten but Monica Niculescu remains forever.

    Great stuff about Aga Radwanska and others in the same article.

    9. Alison Riske is up and running on Substack, too. Her first update is about all things Charleston.

    10. RIP Juan Aguilera, 1990 Hamburg champion. He peaked at #7 in the world, scored seven top-ten wins, and never made the trip to Australia.

    11. This month’s match video is the 2004 US Open third-rounder between Venus Williams and Chanda Rubin:

    Venus wasn’t playing her best tennis–she lost in the next round to Lindsay Davenport–but it was a good effort from Chanda nonetheless. I happened to see one of Rubin’s earlier-round matches that year on a side court. All I remember is one of the few other fans, with a thick Caribbean accent, incessantly shouting “Go Chanda!”

    12. I almost scratched this monthly roundup so I could write about Francisco Cerundolo today instead. I can’t stop thinking about his position on this graph from my Mensik post:

    Cerundolo is even more of an outlier than Mensik, just in the opposite direction. He’s a bit below average in putting first serves away when the return comes back, but he’s better at converted in-play second serves than anyone else on tour.

    This isn’t exactly the same as second-serve winning percentage, but it’s closely related. The Argentinian blew everybody away in the more standard category in Miami:

    The streak lasted even a bit longer: Cerundolo won 70% of second-serve points in the first set of his quarter-final against Grigor Dimitrov. Alas, he finally came back to earth–37% in the final two sets–though he nearly won the match anyway. If he can keep this up away from the South American Slam, it will merit a longer treatment.

    13. Here’s some new (in English) research into the Sumarokov-Elstons, the first family of pre-Soviet Russian tennis.

    14. One more that we lost this month: RIP John Feinstein. He was better known as a golf and basketball writer, but he covered tennis as well, including the 1991 book Hard Courts. Pete Bodo wrote a nice remembrance, and I enjoyed this thread from a colleague.

    15. Now that Alexandra Eala has ignited tennis mania in the Philippines, how long until we get a WTA event in Manila? There has been some tennis in the islands for more than 100 years, and competitive women’s tennis back to at least 1935. Eala is surely the best from the country so far, though I did notice that early champ Minda Ochoa upset visiting American Helen Marlowe–a two-time national junior finalist–in 1936.

    16. Forgot this one last month: In her WTA debut in Austin, Malaika Rapolu got called for a time violation on return. I know it’s not unprecedented, but it’s rare enough to be a harsh welcome to the tour. Now, umpires just need to apply the same standards to players inside the top 500.

    17. Tennis execs are surely paying attention to the TGL, an indoor, team-based, simulator-driven golf tournament that just wrapped up. With an eleven-week season, it requires more buy-in than any tennis upstart is going to get; in that sense, it more closely resembles 1970s-era World Team Tennis. The high-tech approach seems to have worked, deviating from the traditional version of the sport more than any tennis exhibition ever has.

    18. One more non-tennis note: I recently read James Astill’s The Great Tamasha, about Indian cricket from its beginnings to the (then–the book was published in 2014) new Indian Premier League. Another example of a sport ramping up fan engagement and shortening formats, and succeeding.

    This, though, is what will stick with me:

    [Bengali sociologist Ashis] Nandy shook his head. ‘I don’t see much of cricket in this IPL business. It is simply a degraded form of the game. What is the point of it? Is it an effort to catch up with other sports? Why? So many sports are so similar. Why can they not allow us to have one game to be different?’ He paused, and gazed into space. He looked bereft.

    19. Someone complained about the lack of music last month, so here ya go:

    * * *

    Subscribe to the blog to receive each new post by email:

     

    Jakub Mensik, Giant Killer

    Watch out

    On Saturday, Jakub Mensik did it again. Jack Draper was coming off an Indian Wells title, the fortnight of his career, but Mensik was a little bit better. Both sets went to tiebreaks, and twice, at six-all, the 19-year-old Czech took his serving to a new level. He won 14 of 19 tiebreak points and sent the Brit home early.

    After such an assured performance, Mensik’s third-rounder felt like a gimme. Roman Safiullin gave him two looks at break points, and that’s all he needed. Behind another monster serve barrage, the Czech waltzed into the fourth round, 6-4, 6-4.

    Mensik currently stands outside the top 50, but his ranking doesn’t tell the full story. For one thing, he made his top-50 debut late last year, and his Miami points will almost certainly be enough for him to return. Beyond that, he has proven that he fears no one on tour. Draper was his 6th top-ten win in 11 tries. What’s more, Mensik won a set in three of the five losses, including a meeting in Shanghai last fall with Novak Djokovic.

    Djokovic called him “one of the best servers we have in the game.” Indeed, since the US Open last year, the six-foot, four-inch Mensik is cracking aces on more than 15% of his serve points. Only Giovanni Mpetshi Perricard and Quentin Halys rate better among tour players. He has taken things to a new level in Miami. In each of his three matches–against Roberto Bautista Agut, Draper, and Safiullin–he has hit an ace on at least 26% of his serve points. That’s Reilly Opelka-level serve dominance, and even Opelka hasn’t posted three straight ace rates like that since 2022.

    Mensik is one of the most exciting prospects on tour, yet Joao Fonseca-mania doesn’t leave much attention to anyone else. What do we make of those top-ten wins… and the non-top-ten losses that have kept him on the edge of the top 50? How should we rate the rest his game–you know, those occasions when he doesn’t end the point with a first serve? Let’s dig in.

    Proof of concept

    Here is the top-ten record:

    Pretty good for someone with another five months left in their teens.

    Draper wasn’t the first top-tenner that Mensik overpowered. In the six wins, the Czech held serve 90% of the time, winning three-quarters of first serve points. Djokovic and Alex de Minaur figured out how to neutralize the serve, but lesser returners (read: most other humans) have not.

    Even before the Miami upset, Mensik was just the 21st player since the beginning of the ATP rankings to win at least five of his first ten meetings with top-tenners. (I’m excluding players who were already established in 1973, when the points table debuted.) He’s just the 12th ever to win six of eleven. Here’s the full list:

    Player               First 10  First 11  
Alberto Mancini           7-3       7-4  
Miloslav Mecir            7-3       7-4  
Fernando Gonzalez         6-4       7-4  
Marc Kevin Goellner       6-4       7-4
Lleyton Hewitt            6-4       6-5  
Jakub Mensik              5-5       6-5  
Ugo Humbert               5-5       6-5  
Marcos Baghdatis          5-5       6-5  
Marat Safin               5-5       6-5    
Carlos Moya               5-5       6-5  
Chris Woodruff            5-5       6-5  
Magnus Larsson            5-5       6-5  
Boris Becker              5-5       6-5  
Fabian Marozsan           5-5       5-6  
Aslan Karatsev            5-5       5-6  
Matteo Berrettini         5-5       5-6  
Reilly Opelka             5-5       5-6  
Mardy Fish                5-5       5-6  
Nicolas Kiefer            5-5       5-6  
Henrik Holm               5-5       5-6  
Greg Holmes               5-5       5-6

    It’s a strong list, if a bit scattershot. We have all-time greats, plus Aslan Karatsev and Greg Holmes, who apparently upset both Mats Wilander and Jimmy Connors. The playing styles might tilt a bit toward heavy hitting and big serving, but not overwhelmingly so.

    I mention playing styles because rocket serves, like Mensik’s, have a way of turning matches into coin flips. If the serves aren’t coming back, it doesn’t matter how well the guy returns. Other skills fall by the wayside: We’re headed for a tiebreak. Apart from a pair of early breaks, that’s what happened in the Draper match. John Isner won three of his first ten top-ten encounters, and Opelka earned a spot on this list.

    Everything else

    When the serves do come back, though, it’s anybody’s ballgame, top-ten opponent or not. For Mensik, just about everything apart from the first serve is a relative weakness. In the last 52 weeks, he has won just 47.4% of his second-serve points, worse than 49 of the top 50 players. (Pedro Martinez is the one guy with a sub-Mensik number.)

    The Czech has gotten accolades for his backhand, but it’s not really a weapon. While it doesn’t hold him back, it rates about tour average by my Backhand Potency (BHP) metric. His Forehand Potency is the real issue. At just +1.1 per 100 forehands, he ranks ahead of only a few of his colleagues, including Opelka, Mpetshi Perricard, and Hubert Hurkacz. Hurakcz has proven that it’s possible to hang around the top of the game without much help from the forehand, but it’s a narrow path to follow.

    All this adds up to some painful numbers in rallies. I was going to say “long rallies,” but Mensik starts to see a disadvantage about as soon as the word “rally” comes into play. In eleven charted matches over the last 52 weeks (not counting the Draper upset), here are how his results shake out by rally length:

    Length      Win%  
1-3 shots  52.2%  
4-6 shots  45.3%  
7-9 shots  41.9%  
10+ shots  42.0%

    52% on short points is great! That was enough to crack the top ten list when I looked at the same category last week in the context of Draper’s excellence. Since these stats encompass both serve and return, it tells us that he’s cleaning up more of his own quick points than his opponents can manage of their own.

    The rest of the story, though, is bleak. He ranks near the bottom in all three of the other categories. If we lump them together, he win the fewest points of anyone with at least ten charted matches in the last year:

    Player              1-3 W%  4+ W%  
Jakub Mensik         52.2%  43.8%  
Mpetshi Perricard    51.6%  43.8%  
Zhizhen Zhang        48.5%  44.1%  
Jiri Lehecka         51.8%  44.2%  
Ben Shelton          50.5%  44.7%  
Hubert Hurkacz       55.0%  45.4%  
Lorenzo Sonego       52.5%  45.5%  
Tallon Griekspoor    49.8%  46.1%  
Flavio Cobolli       44.9%  46.6%  
Alexei Popyrin       50.4%  46.8%  
…                                  
Jack Draper          53.3%  48.8%  
…                                  
Stefanos Tsitsipas   50.5%  50.6%  
…                                  
Alexander Zverev     53.0%  53.1%  
…                                  
Novak Djokovic       53.7%  54.9%  
Carlos Alcaraz       52.5%  55.8%  
Jannik Sinner        54.4%  57.0%

    Somehow, it gets even worse. With enough short points, weak long-rally skills are survivable. Yet Mensik plays more long points than most of these guys in the bottom ten. The 1-to-3-shot category accounts for less than 63% of his points, while it makes up more than 70% of Mpetshi Perricard’s. Even Jiri Lehecka, hardly an extreme case like GMP, comes in at 66%.

    Second to last

    Mensik is hardly an elite returner, but he is good enough for now. He has won about 37% of his return points over the last 52 weeks, a rate that–coupled with strong serving–is sufficient to get him into the top ten. Despite his relatively low ranking, he has posted those numbers against high-quality competition. His median opponent has been stronger than those faced by Stefanos Tsitsipas or Casper Ruud.

    The immediate concern for the Czech is his second serve. I mentioned earlier that he wins barely 47% of those points. Ben Shelton, who wins exactly as many first-serve points as Mensik does, converts 55% of his seconds. While that’s unusually good, nearly every player in the same first-serve territory wins at least 51% behind the second serve.

    This is a good time to remember that Mensik is 19. He hasn’t been six-foot-four for long. It’s possible that his second serve will look entirely different in two years than it does today. He’ll certainly hope so. He misses more than 12% of his seconds, a double-fault rate that would be acceptable only if he were taking chances and reaping the rewards of those risks. At the moment, he’s just struggling.

    The second-serve weakness is more than enough to flip the outcome of a match. In the last year, when Mensik has landed at least 60% of his first serves, his record is 16-5. Under 60%, it’s 12-17.

    The root of the problem is what happens when the second serve comes back. The Czech’s second delivery isn’t yet strong enough to generate many easy plus-one opportunities, and his ground game isn’t sturdy enough to make up for it. When his first serves come back, his results are close to tour average. But when the second serve comes back, he ranks at the very bottom of the table.

    This scatterplot shows every player with at least ten charted matches over the last year. It compares each player’s win rate when their first serves come back with their results when second serves come back. Guys below the dotted line see relatively worse outcomes behind their second serve:

    There’s no single limitation that is depressing Mensik’s second-serve results. The positive spin on that is that he has a lot of areas with room to improve. Even an average second serve–seemingly a reasonable goal for a man with such an imposing first–would probably make him a top-20 player.

    The way forward

    Nothing makes it easier to dream about a big future in tennis than a monster serve. Any list of overrated youngsters is going to be littered with powerful teens who remained too one-dimensional to convert all their aces into tournament victories.

    That, I think, is the low-end forecast for Jakub Mensik. If he simply keeps doing what he’s doing, he could be a top-40 or top-50 player for a long time. His first serve is that good, and the rest of his game is adequate. He probably wouldn’t continue to win half of his top-ten meetings, since the game’s top players would have more time to figure him out.

    On the other hand, again, he’s 19! The difference between his first- and second-serve results is a statistical oddity, which could mean either that he is uniquely one-dimensional, or that he has plenty of room to develop. The latter seems more likely. He may remain limited on return, but a second serve to match his first would make him near-unbreakable. That’s the recipe for a lot more top-ten wins, and possibly for a single-digit ranking of his own.

    * *

    Subscribe to the blog to receive each new post by email: