Forecasting Andy Murray, Doubles Specialist

We are three weeks into the mostly-triumphant doubles comeback of Andy Murray. In his first week back, he raced to the Queen’s Club title with Feliciano Lopez. A week later, he paired Marcelo Melo and lost in the first round. At Wimbledon, he is partnering Pierre-Hugues Herbert, with whom he has already defeated the only-at-a-slam duo of Marius Copil and Ugo Humbert.

Today in the second round, Herbert/Murray face a sterner test: sixth-seeded team Nikola Mektic and Franco Skugor. The betting markets heavily favored Herbert/Murray going into the contest, but we have to assume that punters (including an unusually high number of casual ones) are probably overrating the familiar name on his home turf.

D-Lo to the rescue

Let’s see what D-Lo (Elo for doubles!) says about today’s match. D-Lo treats each team as a 50/50 mix of the two players, and adjusts each player’s rating after every match, depending on the quality of the opponent. It also very slightly regresses both partners to the team average after each match, because it’s impossible to know how much each player contributed to the result.

Herbert is D-Lo’s top doubles player in the world on hard and clay courts, though he falls to 6th in the 50/50 blend of overall and grass-specific ratings used for forecasting. Murray, thanks to his run at Queen’s, is up to 54th in the blend, though that’s really more like 40th among players in the draw, since several injured and recently-retired players are clinging to high D-Lo ratings.

Mektic and Skugor are credible specialists, as indicated by their ATP ranking. They are 24th and 26th in the D-Lo, respectively. Combined, the two teams’ ratings are quite close: 1773 for Herbert/Murray to 1763 for Mektic/Skugor. In a best-of-three match, a difference of 10 points translates to a 51.4% edge for the favorites. In best-of-five, the better team is always more likely to come out on top, though with such a small margin it barely matters. Here, the best-of-five number is 51.6%.

Versus the pack

How does a team rating of 1773 compare to the rest of the remaining field? Entering Saturday’s play, 22 men’s doubles pairs were still in the draw. As I write this, Lopez and Pablo Carreno Busta are the only additional team to have been eliminated, reducing the field to 21.

Here are the combined D-Lo ratings of these teams. The rank shown for each player is based on the 50/50 blend of overall and grass rating used for forecasting.

Team D-Lo  Rank  Player             Rank  Player             
1873       2     Mike Bryan         3     Bob Bryan          
1858       4     Lukasz Kubot       7     Marcelo Melo       
1836       9     Raven Klaasen      10    Michael Venus      
1817       8     John Peers         17    Henri Kontinen     
1802       12    Nicolas Mahut      22    E Roger-Vasselin   
1788       18    J S Cabal          19    Robert Farah       
1773       6     P H Herbert        54    Andy Murray        
1764       15    Oliver Marach      36    Jurgen Melzer      
1763       24    Nikola Mektic      26    Franco Skugor      
1757       20    Rajeev Ram         33    Joe Salisbury      
1747       23    Horia Tecau        41    Jean Julien Rojer  
1709       42    Maximo Gonzalez    46    Horacio Zeballos   
1695       29    Ivan Dodig         88    Filip Polasek      
1681       58    Marcus Daniell     62    Wesley Koolhof     
1677       50    Frederik Nielsen   77    Robin Haase        
1644       81    Marcelo Demoliner  90    Divij Sharan       
1637       84    A Ul Haq Qureshi   99    Santiago Gonzalez  
1596       106   Philipp Oswald     123   Roman Jebavy       
1575       101   Mischa Zverev      184   Nicholas Monroe    
1533             Jaume Munar        216   Cameron Norrie     
1517       177   Marcelo Arevalo    214   M Reyes Varela

Herbert/Murray rank 7th among the surviving pairs. The combined rating of 1773 makes them competitive against anyone. The 100-point difference separating them and the Bryans gives them a 33% chance of pulling off a best-of-five upset, while the 29-point gap between them and Nicolas Mahut/Edouard Roger Vasselin translates to a 45/55 proposition.

Fortunately for the French-British pair, they won’t have to play a higher-rated team for some time. If they win today, they’ll face the winner of Dodig/Polasek vs Zverev/Monroe. The first of those teams is rated 80 points lower than Herbert/Murray (64% odds for the favorites), and the second is 200 points lower (81% for the faves). The three teams that could advance to become the quarter-final opponent for Herbert/Murray are all rated lower than Dodig/Polasek.

The draw certainly favored Sir Andrew. Yes, the 1859-rated Pavic/Soares duo crashed out in their section, but even before that, three of the best teams–Bryan/Bryan, Kubot/Melo, and Mahut/Roger-Vasselin–were stuck together in another quarter. While no men’s doubles match is a sure thing, the path is clear for Herbert/Murray to reach the final four.

Beyond Wimbledon

Does Murray have what it takes to become a full-time doubles specialist? Taking his Queen’s Club title into account, his overall D-Lo is already up to 36th best on tour, just ahead of Skugor, and several places better than Roland Garros co-champ Kevin Krawietz. Jurgen Melzer, another excellent singles player making of a go of it on the doubles circuit, is ranked 20 places lower, with a D-Lo 40 points less than Murray’s.

The short answer, then, is yes. It must be noted, though, that he isn’t the best choice among the big four to have a successful post-singles career as part of a team. That honor goes overwhelmingly to Rafael Nadal. Nadal’s career peak D-Lo is 100 points higher than Murray’s, and even his grass-court rating–based, admittedly, on some old results–is 70 points higher. Aside from the injured doubles wizard Jack Sock, Nadal is the best active player absent from the Wimbledon draw.

So, Murray/Nadal, Wimbledon 2021 champions? Sounds good to me–as long as Herbert relinquishes his new partner and finally commits to focusing on singles.

Let Bernie Keep His Money

Italian translation at settesei.it

On Tuesday, Bernard Tomic lost his first-round match at Wimbledon to Jo-Wilfried Tsonga. No surprise there: My forecast gave Tsonga a 64% chance of advancing, and that didn’t even take into account Tomic’s shaky health, which has caused him to retire from matches twice in the last six weeks.

Tomic-Tsonga immediately made the news, and for the wrong reasons. The Australian lost, winning only seven games. Ignominiously, the match lasted only 58 minutes, the shortest at Wimbledon since Roger Federer needed only 54 minutes to thump Alejandro Falla back in 2004.

The All England Club responded this morning, announcing that Tomic would lose his prize money. Officially, he “did not perform to the required professional standard.”

Fast and insufficiently furious

I don’t know whether Tomic performed to the required professional standard, because there’s no exact definition of “professional standard.” I suspect it’s some combination of the following:

  • The player lost badly
  • The player has a reputation for tanking
  • The match got a lot of attention so we have to be seen doing something about it

What I do know is that Wimbledon officials are looking at the wrong number. Yes, 58 minutes is an extremely fast three-set match. But Tomic–even when he’s fully engaged and playing his best–is probably the quickest player on tour, often serving as soon as a ballkid gets him the ball. Tsonga also plays fast. Neither player is a good returner, and the Frenchman is a devastating server on a fast surface, so the points were always going to be short.

The more appropriate metric, then, is points played. Tomic and Tsonga contested 125, which is considerably less headline-grabbing than the time on the clock.

Fines all around!

Suddenly, Tomic-Tsonga doesn’t stand out as much. Since 2000, there have been 77 other men’s grand slam matches that required 125 points or less. That’s almost exactly one per slam. The list includes two quarter-finals, three semi-finals, and the 2003 Australian Open title match, in which Andre Agassi dispatched Rainer Schuettler in 76 minutes, needing only 123 points. If we expand our view to matches with fewer than 130 points, we’re looking at another 45 matches, including both of this year’s Australian Open semi-finals.

Simply put: It is not unusual for a men’s slam match to be decided with 125 points. Really good players sometimes lose that fast. It just doesn’t usually attract so much attention, because on average, 125 points takes an hour and 21 minutes to play.

Of course, there are plenty of one-sided contests in the women’s draw, as well. 125 points is about 42 per set, so the “Tomic line” is at 83 or 84 points for a best-of-three match. Since 2003, there have been 235 women’s singles matches of 83 points or less, including five at this year’s French Open alone. (Ironically, Anna Tatishvili’s loss to Maria Sakkari, which triggered its own unprecedented fine, lasted 93 points and 28 minutes per set.)

Reactionary

All of this isn’t to say that Tomic tried his hardest on Tuesday, or that he “deserves” £45,000 in an ethical sense. If tournament referees made it a practice to review video of every first-round match and dock the prize money of the one player who competed most lackadaisically, then sure, the Australian is probably that guy at Wimbledon this year.

But that’s not how it works. The “professional standard” clause is almost never invoked. Had Tomic frittered away more time between points in order to push this match over the one-hour mark, or the offender had been a player with a less checkered past, we wouldn’t be talking about it now.

If the All England Club were focused on the right metric–the amount of tennis played, not how long it took–Bernie’s speedy, casual style of play wouldn’t be in the headlines. After all, there’s another casual, mercurial Australian with a poor return game who deserves more of our attention today.

Visualizing Trends in Net Play Across Five Decades of Grass Court Tennis

Earlier this week, I wrote about one aspect of the long-term decline in net play: the widespread belief that approaching the net is more difficult now because fewer players have a weaker side. I presented evidence indicating that most players still have a weaker side, which suggests that all groundstrokes–on both strong and weak sides–have gotten stronger, making net play a riskier proposition.

If that is true, it is reasonable to assume that passing shot winners are more frequent (relative to the number of net approaches), and perhaps that volleys are more aggressive, resulting in more first-volley winners and first-volley errors. More powerful and precise strokes should, on balance, make net points shorter than they used to be.

We can begin to test these theories using the extensive shot-by-shot records assembled by the Match Charting Project (MCP). MCP data includes every men’s Wimbledon final and semi-final back to 1990, as well as many elite-level grass court matches from the 1970s and 80s. For the purposes of today’s study, I will use only Wimbledon semi-finals and finals, plus a handful of other grass court matches from 1970-89 to complement the sparser Wimbledon data. This way, we know we’re comparing the elites of various generations to one another.

Contemporary net approaches

Let’s start by looking at what happens in a 2010s Wimbledon’s men’s final or semi-final when a player approaches the net. I’m excluding serve-and-volley points, and will do so throughout. I’m also excluding approach shot winners, which are often little more than gestures in the direction of the net following a big shot. (Even when they’re not, it can be difficult for charters to distinguish between approach and non-approach winners.) Thus, we’re looking at about 1,250 net approaches in which the other player got his racket on the ball.

The ball came back almost 73% of the time, and on slightly more than half the points, the approaching player put his first volley (or smash, or whatever shot he needed to hit) in play. 19% of the points saw a second passing shot attempt put in play, and nearly 12% had a second net shot keep the point going. About 1 in 30 approach-shot points continued even longer, forcing the the netman to contend with a third pass attempt.

The following visualization is a Sankey diagram showing how these net points developed. “App” stands for approach, “Unret” for “unreturned,” “Pass1” for “first passing shot,” “V1” for “first volley,” and so on. Mouse over any region of the diagram for a brief summary of what it represents.

2010s Wimbledon Net ApproachesApps → Pass1 In: 72.6%Pass1 In → V1 In: 51.2%V1 In → Unret V1: 32.1%Unret V1 → App’er Wins: 32.1%Apps → Unret App: 27.4%Unret App → App’er Wins: 27.4%Pass1 In → Unret Pass1: 21.4%Unret Pass1 → App’er Loses: 21.4%V1 In → Pass2 In: 19.1%Pass2 In → V2 In: 11.6%V2 In → Unret V2: 8.4%Unret V2 → App’er Wins: 8.4%Pass2 In → Unret Pass2: 7.5%Unret Pass2 → App’er Loses: 7.5%V2 In → Rally Continues: 3.2%Rally Continues → App’er Loses: 1.9%Rally Continues → App’er Wins: 1.3%Apps: 100%Apps: 100%Unret App: 27.4%Unret App: 27.4%Pass1 In: 72.6%Pass1 In: 72.6%V1 In: 51.2%V1 In: 51.2%Unret Pass1: 21.4%Unret Pass1: 21.4%Unret V1: 32.1%Unret V1: 32.1%Pass2 In: 19.1%Pass2 In: 19.1%V2 In: 11.6%V2 In: 11.6%Unret Pass2: 7.5%Unret Pass2: 7.5%Unret V2: 8.4%Unret V2: 8.4%Rally Continues: 3.2%Rally Continues: 3.2%App’er Wins: 69.2%App’er Wins: 69.2%App’er Loses: 30.8%App’er Loses: 30.8%

There’s a lot of information in the graphic, and it may not be entirely intuitive, especially hindered by my clunky design. Each region is sized based on what fraction of points developed in a certain way. As the regions move toward the right side of the diagram, they as classified by whether the approaching player won the point. As we can see, in the 2010s sample, these approach shots resulted in points won about 69% of the time.

The golden era

To compare eras, we need more than just one decade’s worth of data. I separated the approach shots by decade (grouping together the 70s and 80s), and the most distinctive era turned out to be the 1990s, when Pete Sampras ruled the roost and many of his challengers were equally aggressive.

Far more points were opened with a serve-and-volley: almost 81% in the 1990s compared to 7% in this decade. Even with the server claiming the net so early and so often, there were still many more non-serve-and-volley net approaches two decades ago. Then, there were about 85 “other” net approaches per match; this decade, there have been about 27. Thus, it is reasonable to assume that the typical net approach started from a less favorable position. These days, players only approach when the point has developed in a particularly inviting way.

Here is another diagram, this one showing what happened following 1990s net approaches:

1990s Wimbledon Net ApproachesApps → Pass1 In: 65.5%Pass1 In → V1 In: 44.4%Apps → Unret App: 34.5%Unret App → App’er Wins: 34.5%V1 In → Unret V1: 23.9%Unret V1 → App’er Wins: 23.9%Pass1 In → Unret Pass1: 21.1%Unret Pass1 → App’er Loses: 21.1%V1 In → Pass2 In: 20.5%Pass2 In → V2 In: 10.7%Pass2 In → Unret Pass2: 9.8%Unret Pass2 → App’er Loses: 9.8%V2 In → Unret V2: 7.8%Unret V2 → App’er Wins: 7.8%V2 In → Rally Continues: 2.9%Rally Continues → App’er Loses: 1.8%Rally Continues → App’er Wins: 1.1%Apps: 100%Apps: 100%Unret App: 34.5%Unret App: 34.5%Pass1 In: 65.5%Pass1 In: 65.5%V1 In: 44.4%V1 In: 44.4%Unret Pass1: 21.1%Unret Pass1: 21.1%Unret V1: 23.9%Unret V1: 23.9%Pass2 In: 20.5%Pass2 In: 20.5%V2 In: 10.7%V2 In: 10.7%Unret Pass2: 9.8%Unret Pass2: 9.8%Unret V2: 7.8%Unret V2: 7.8%Rally Continues: 2.9%Rally Continues: 2.9%App’er Wins: 67.3%App’er Wins: 67.3%App’er Loses: 32.7%App’er Loses: 32.7%

It’s striking to see that, back when net play was much more common, with a master such as Sampras dominating our sample, net approaches were less successful than they are today, resulting in a 67% win rate instead of 69%. However, it’s tough to know how today’s players–even a confident aggressor like Roger Federer or a volleying wizard like Rafael Nadal–would fare if they came forward four times as much. Assuming they pick their spots wisely, their success rate would be lower than 69%. The only question is how much lower.

Contrary to my inital hypothesis, passing shots seemed to be higher-risk and higher-reward in the 1990s than in the 2010s. Two decades ago, only 65.5% of initial passing shot attempts were put in play (compared to 72.6% today), though nearly as many of those attempts resulted in winners (21.1% to 21.4%). It was the volleyers who were either more conservative or less powerful in the 1990s. Then, barely half of first volleys ended the point in the netman’s favor; now, the number is closer to 60%. Again, this could be because today’s players pick their spots more carefully, allowing them to hit easier first volleys.

The early days

We’ve seen how net approaches developed in the 1990s and the 2010s. It would be reasonable to assume that the 1980s (with several late ’70s matches thrown in) were like the 1990s, but more so. Instead, the results are more of a mixed bag, with some characteristics that look like the ’90s, and others that are closer to today’s numbers.

Here is the diagram:

1980s Wimbledon Net ApproachesApps → Pass1 In: 70.4%Pass1 In → V1 In: 48.9%Apps → Unret App: 29.6%Unret App → App’er Wins: 29.6%V1 In → Pass2 In: 26.1%V1 In → Unret V1: 22.8%Unret V1 → App’er Wins: 22.8%Pass1 In → Unret Pass1: 21.5%Unret Pass1 → App’er Loses: 21.5%Pass2 In → V2 In: 15.6%V2 In → Unret V2: 10.8%Unret V2 → App’er Wins: 10.8%Pass2 In → Unret Pass2: 10.5%Unret Pass2 → App’er Loses: 10.5%V2 In → Rally Continues: 4.8%Rally Continues → App’er Loses: 2.8%Rally Continues → App’er Wins: 2%Apps: 100%Apps: 100%Unret App: 29.6%Unret App: 29.6%Pass1 In: 70.4%Pass1 In: 70.4%V1 In: 48.9%V1 In: 48.9%Unret Pass1: 21.5%Unret Pass1: 21.5%Unret V1: 22.8%Unret V1: 22.8%Pass2 In: 26.1%Pass2 In: 26.1%V2 In: 15.6%V2 In: 15.6%Unret Pass2: 10.5%Unret Pass2: 10.5%Unret V2: 10.8%Unret V2: 10.8%Rally Continues: 4.8%Rally Continues: 4.8%App’er Wins: 65.2%App’er Wins: 65.2%App’er Loses: 34.8%App’er Loses: 34.8%

In the 1980s, nearly as many passing shot attempts were put in play as they are today, in contrast to the lower rate during the 1990s. First volleys are a similar story. When passing shot attempts came back, approaching players put a volley (or other net shot) back in the court about 70% of the time–similar numbers in the 1980s and 2010s, but a couple percentage points higher than in the 1990s.

What is different is what happened next. In the 1980s, if the approaching player put his first volley back in play, it came back again 53% of the time. That rate is one of the few clear trends over time: It fell to 46% in the 1990s, 45% in the 2000s, and 37% in the 2010s. As a result, the ’80s saw far more second volleys and points that extended even further, compared to more recent eras. The lack of first-volley putaways meant that net approaches only converted into points won about 65% of the time.

A cautious narrative

There is no simple explanation that accounts for all of these numbers, because we are not seeing the direct result of a single factor, like the shift from wooden rackets or to more topspin-friendly string. Technological changes certainly have an impact, but as soon as the balance between approacher and opponent shifts, players adjust their strategy accordingly.

For instance, the rate of points won on net approaches appears to have steadily increased, from 65% in the 1980s to 67% in the 1990s to 69% today. The first rise could be attributed to racket technology, which gave aggressors more power and control. But the second rise came over a time period in which string technology offered more help to defenders. The higher rate of approach points won isn’t because players are better at it, it’s because they picked their spots more carefully.

What we might focus on instead, then, is how much these diagrams look alike, even though they represent vastly different eras. While there isn’t exactly a net-approach-strategy equilibrium that has held through the decades, player decision-making has kept these rates from varying too wildly. If passing shot winners start going up, we’ll probably see even fewer approaches–with the remaining approaches in still more favorable moments–or a continued increase in the percentage of approaches to the backhand side. That’s another clear trend over the last few decades, but it’s a topic for another day.

Rather than succumbing to nostalgia and bemoaning the decline of net play, it’s better to celebrate the adaptability of tennis players at the highest level. While the game a whole has become more defensive, backcourt denizens from Bjorn Borg (94 approaches per charted grass-court match) to Novak Djokovic (21 approaches per match) have reminded us that adjustments work in both directions. With parameters such as technology, surface, and opponent skills constantly changing, we can’t expect winning strategy to remain the same.

Thanks to SankeyMATIC for making it easy to create the diagrams.

Economist: Cori Gauff announces herself at Wimbledon

At the Economist’s Game Theory blog, I wrote about Cori Gauff’s historic upset of Venus Williams:

IT IS hard to avoid the impression that the tennis world has witnessed a changing of the guard. On July 1st , the opening day of the 2019 Championships at Wimbledon, Cori Gauff, a 15-year-old American prospect, upset the five-times champion Venus Williams in straight sets. Ms Williams, aged 39, was not the highest-ranked player to fall on the first day of the tournament; that honour belonged to the reigning US Open champion, Naomi Osaka, the second seed. But no first-round winner has garnered more attention than Ms Gauff, whose youth causes her to establish new records every time she steps on court.

Read the whole thing.

Net Play Has Declined, But This Isn’t Why

Italian translation at settesei.it

Wimbledon is here, so it’s time for another cycle of media commentary about the demise of net play, especially the serve-and-volley. The New York Times published a piece by Joel Drucker last week that covered this familiar territory, cataloguing various reasons why the game has changed. Racket and string technology, along with tweaks to the All England Club playing surface, are rightfully on the list.

But the first reason Drucker gives is the rise of the two-handed backhand and, by extension, the threat posed by players with weapons on both sides:

In May 1999, 43 of the top 100 male players in the world hit their backhands with one hand. As of June 2019, there were 15. According to Mark Kovacs, a sports science consultant and tennis coach, “Most players used to have a weaker side, usually the backhand. And the two-handed backhand changed that completely. It doesn’t give you a spot you can hit to.”

I’m more interested in the “weaker side” argument than the fortunes of the one-handed and two-handed backhands. Many players who still use one-handers, such as Stan Wawrinka, would rightly bristle at a claim that their shots are weak. In terms of effectiveness, the contemporary one-handed shot might have more in common with a two-hander of old than the all-slice, only-defensive backhand favored by many pros in the 1970s and 1980s.

Both sides, now

The “weaker side” argument can be slightly rephrased into a research question: For contemporary players, is there a smaller gap between forehand effectiveness and backhand effectiveness than there used to be?

To answer that, we need a working definition of “effectiveness.” Long-time readers may recall a stat of mine called “potency,” as in “backhand potency” (BHP) or “forehand potency” (FHP). It’s a simple stat, using data derived from the shot-by-shot records of the Match Charting Project, calculated as follows:

BHP approximates the number of points whose outcomes were affected by the backhand: add one point for a winner or an opponent’s forced error, subtract one for an unforced error, add a half-point for a backhand that set up a winner or opponent’s error on the following shot, and subtract a half-point for a backhand that set up a winning shot from the opponent.

The same procedure applies to forehand potency and slice potency. The weights–plus one for some shots, plus a half point for others, and so on–are not precise. But the results generally jibe with intuition. Across 3,000 charted ATP matches, an average player’s results from a single match are:

  • Forehand potency (FHP): +6.5
  • Backhand potency (BHP): +0.8
  • Slice potency (SLP): -1.3
  • Backhand side potency (BSP): -0.5

The first three stats isolate single shots, while the final one combines BHP and SLP into a single “backhand side” metric. All of these exclude net shots, and since forehand slices are so rare, I’ve left those out of today’s discussion as well.

The forehand reigns

The numbers above shouldn’t come as a surprise. The average ATP player has a stronger forehand than backhand, regardless of how many hands are on the racket for the latter shot. Novak Djokovic possesses one of the best backhands in the history of sport, but the gap between his FHP and BSP numbers is greater than average: +11.3 per match for the forehand, and +2.5 for the backhand, resulting in a difference of 8.8. Even a backhand master reaps more rewards on his other side.

The Match Charting Project has at least three matches worth of data for 299 different men across several generations, spanning from Vitas Gerulaitis to Jannik Sinner. Only 30 of them–about one in ten–gain more points on their backhand than on their forehands, and for half of that minority, the difference is less than a single point. It’s a diverse group, including Pat Cash, Jimmy Connors, Guillermo Coria, Ernests Gulbis, Daniil Medvedev, and Benoit Paire. This mixed-bag minority doesn’t provide much evidence to settle the question.

Proponents of the “weaker side” argument often point to the arrival of Lleyton Hewitt as a turning point between the net-play-was-feasible era and the approach-at-your-peril era. Others might point to Andre Agassi. As it turns out, both of these figures are surprisingly average.

The Match Charting Project has extensive records on both men. Hewitt’s forehand was worth +10.0 per match, while his backhand and slice combined for +2.9. That’s a difference of 7.1, a bit greater than average, though less than Djokovic’s. Agassi’s FHP was good for +13.0 per match, compared to a BSP of +6.8. That’s a difference of 6.2, even closer to the mean than Hewitt. Ironically, that gap is almost identical to that of Pete Sampras, whose FHP of +6.3 and BSP of -0.1 were equally spaced, even though his groundstrokes were considerably less effective.

Comparing eras

We can’t answer a general question about trends over time simply by calculating shot potencies for individual players, no matter how pivotal. Instead, we need to look at the whole population.

First, a quick note about our data: The Match Charting Project is extremely heavily weighted toward current players. Our sample of 300 players consists of only 40 whose careers were mostly or entirely in the 20th century, and 30 more whose matches mostly took place in the first decade of this century. Thus, the averages mentioned above are skewed toward the 2010s. That said, the 70 “older” players in the sample are the most prominent–the guys who played in major finals and semi-finals, and Masters finals. If there has been a marked trend across decades, those players should help us reveal it.

The earlier players in our sample are, in fact, quite similar to the contemporary ones. I ranked the 299 players by the absolute difference between their FHP and their BSP, with the most balanced player ranked 1, and the least balanced ranked 299. I looked at two subgroups: the 52 oldest players in the sample, most of whose careers were fading out when Hewitt arrived; and the 78 players with the most recent matches in the sample.

  • Oldest — Average rank: 143, Average (FHP – BSP): 5.7
  • Most recent — Average rank: 155, Average (FHP – BSP): 6.5

These numbers do not indicate that players used to have a weak side, and now they don’t. They don’t really reflect any trend at all. The difference between forehand effectiveness and backhand side effectiveness has barely changed over several decades.

As further evidence, here is a selection of players who are both well-represented in the Match Charting Project data and noteworthy representatives of their eras. They’re listed in approximate chronological order. Each of the shot-potency numbers is given on a per-match basis, and the final column (“Diff”) is the difference between FHP and BSP–the gap between each player’s forehand and backhand sides.

Player              FHP    BHP   SLP   BSP  Diff  
Bjorn Borg          12.9  11.5  -0.5  11.0   2.0  
Jimmy Connors       6.5    9.1  -0.3   8.9  -2.4  
John McEnroe        2.0   -0.4  -2.1  -2.4   4.4  
Mats Wilander       7.2    6.8  -0.5   6.3   0.9  
Ivan Lendl          10.3   4.0   0.6   4.6   5.7  
Stefan Edberg       1.9    1.8  -1.1   0.7   1.1  
Boris Becker        5.9    2.1  -1.5   0.7   5.2  
Jim Courier         13.3   4.2  -0.3   3.9   9.4  
Michael Stich       2.0    2.0  -3.4  -1.4   3.4  
Michael Chang       9.7    5.0  -0.6   4.4   5.3  
                                                  
Player              FHP    BHP   SLP   BSP  Diff  
Thomas Muster       18.4   2.2  -1.1   1.1  17.3  
Pete Sampras        6.3    0.7  -0.7  -0.1   6.4  
Andre Agassi        13.0   7.2  -0.5   6.8   6.3  
Patrick Rafter      3.5    0.5  -1.6  -1.1   4.6  
Carlos Moya         9.8   -0.9  -1.4  -2.3  12.1  
Lleyton Hewitt      10.0   3.5  -0.6   2.9   7.1  
Guillermo Coria     4.7    6.3  -1.2   5.2  -0.5  
David Nalbandian    8.8    5.6  -1.7   3.9   4.9  
Nikolay Davydenko   7.2    4.4  -1.2   3.2   4.0  
Roger Federer       10.0   0.2  -0.4  -0.3  10.2  
                                                  
Player              FHP    BHP   SLP   BSP  Diff  
Rafael Nadal        15.3   2.6  -1.0   1.6  13.7  
Andy Murray         7.2    2.9  -1.8   1.1   6.1  
Novak Djokovic      11.3   3.4  -0.8   2.5   8.8  
Richard Gasquet     1.9    1.4  -1.4   0.0   1.9  
Stan Wawrinka       6.2    0.5  -1.7  -1.2   7.3  
Kei Nishikori       5.4    3.8  -1.1   2.7   2.8  
Dominic Thiem       9.3   -0.1  -1.6  -1.7  11.0  
Alexander Zverev    3.6    4.2  -1.1   3.0   0.6  
Stefanos Tsitsipas  8.3   -0.9  -2.2  -3.0  11.4  
Daniil Medvedev     1.6    3.3  -1.4   1.9  -0.3 

Not weaker, but weak

These numbers cast a lot of doubt on the “weaker side” hypothesis, that it used to be easier to move forward by approaching an opponent’s less dangerous wing.

Instead, what has probably happened is that for the typical player, both sides got stronger. As a result, the weaker side was no longer flimsy enough to make approaching the net a profitable strategy. Even players with weaker-than-average backhands are now able to hit powerful topspin passing shots. This is essentially the racket-and-string-technology argument, and it seems to me to be the most valid.

There’s no question that tennis has drastically changed in the last few decades. But the conventional explanations for those trends don’t always hold up under scrutiny. In this case, while volleys have been reduced to a vestigial part of the singles game, groundstrokes–on both sides–have only gotten better.

Podcast Episode 68: Wimbledon Preview: Hot Streaks for Pliskova and Fritz, and a Cold Streak for Serve-and-Volley

Episode 68 of the Tennis Abstract Podcast, with Carl Bialik of the Thirty Love podcast, starts with a a deep dive into whether there is still a place for serve-and-volley tennis in today’s game, especially for the most dominant servers. The element of surprise is a factor, but the stats are difficult to crunch, as serve-and-volley points don’t occur randomly, and everyone doesn’t even agree on the definition of a serve-and-volley point! is.

We also cover the highlights of the final Wimbledon warm-up events, starting with the big Pliskova-Kerber WTA final and the all-American ATP title match in Eastbourne. We look at the favorites–Novak Djokovic and Ashleigh Barty–as well as this week’s winners, to see how the fortnight at the All England Club is likely to develop.

Thanks for listening!

(Note: this week’s episode is about 69 minutes long; in some browsers the audio player may display a different length. Sorry about that!)

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Podcast Episode 67: Wimbledon Warm-Up Wins for Federer, Barty, and Andy Murray

Episode 67 of the Tennis Abstract Podcast, with Carl Bialik of the Thirty Love podcast, resumes last week’s discussion about unrestricted in-match coaching, and how technology might drastically change the advice a player receives. We then cover Andy Murray’s successful doubles comeback, and consider what to expect going forward.

Finally, we talk Wimbledon forecasts, taking into account the latest results from Queen’s Club, Birmingham, and the rest. Djokovic remains our men’s favorite, though a handful of new names are forcing us to take notice. New WTA No. 1 Ashleigh Barty has opened up a gap ahead of the rest of the women’s field, making her the top pick amid a very deep field.

Thanks for listening!

(Note: this week’s episode is about 59 minutes long; in some browsers the audio player may display a different length. Sorry about that!)

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Podcast Episode 66: The Grass is Greener, Even For a Few Dirtballers

Episode 66 of the Tennis Abstract Podcast, with Carl Bialik of the Thirty Love podcast, starts with a discussion about Matteo Berrettini, the Italian clay specialist who proved himself a dangerous competitor on the Stuttgart grass last week. We talk about the tactics that work on grass, and how those sometimes overlap with clay-court strategies, despite the differences between the natural surfaces.

We also cover Andy Murray’s return to the doubles court, Murray’s possibly-tour-best lob, the Herbert-Mahut split, the indoor hard court matches at the Nottingham grass court event, the excellent Nottingham final between Caroline Garcia and Donna Vekic, and finally, the US Open’s decision to allow coaching from the stands at this year’s event.

Thanks for listening!

(Note: this week’s episode is about 64 minutes long; in some browsers the audio player may display a different length. Sorry about that!)

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Podcast Episode 65: Rafa! Barty! Krawietz/Mies! Roland Garros in Review

Episode 65 of the Tennis Abstract Podcast, with Carl Bialik of the Thirty Love podcast, celebrates the breakthrough of Ashleigh Barty by discussing what sets her game apart, what might be working for her on clay, and what her future holds. We mark Rafael Nadal’s 12th Roland Garros title with a (futile) search for tennis achievements that compare to Rafa’s French Open dominance. Finally, we consider whether the best tennis players are the best at anything in particular, and whether stats on grand slam websites are anything more than a marketing exercise.

As we mention at the top of this episode, Carl interviewed Roland Garros double champions Kevin Krawietz and Andreas Mies earlier this season. Click here to listen to that Thirty Love episode.

Thanks for listening!

(Note: this week’s episode is about 64 minutes long; in some browsers the audio player may display a different length. Sorry about that!)

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Podcast Episode 64: French Open Final Fours

Episode 64 of the Tennis Abstract Podcast, with Carl Bialik of the Thirty Love podcast, is a special mid-week bonus: a preview of the men’s and women’s semi-finals at Roland Garros. We discuss the unending parade of upsets that has provided us a women’s final four without a single grand slam finalist, as well as the star-studded men’s quartet, including the first Federer-Nadal encounter on clay in six years.

We also touch on the clumsy rescheduling that has left the women’s semis outside the main stadium, and the exciting WTA $125K event happening this week in Croatia.

Thanks for listening!

(Note: this week’s episode is about 58 minutes long; in some browsers the audio player may display a different length. Sorry about that!)

Click to listen, subscribe on iTunes, or use our feed to get updates on your favorite podcast software.