Podcast Episode 20: Five Tournaments, Lots of Decisions

Episode 20 of the Tennis Abstract Podcast, with Carl Bialik of the Thirty Love podcast, is a deep dive into the question of surface preferences and tournament choices, as we straddle two weeks of ATP action in which events are played on both hard and clay, and every competitors needs to weigh his or her own skills against issues like jetlag, prize money, and all-important ranking points. We also discuss the potential of future stars Frances Tiafoe, who picked up his first title in Delray Beach, and Daria Kasatkina, who reached the final in Dubai.

If you were turned off by the audio last week … sorry about that. Our latest experiment didn’t work at all. This episode’s audio is much better. Thanks for listening!

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Update: Thanks to FBITennis, here are timestamps and an outline of this episode:

Schwartzman Cracks Top 20 1:10
Scheduling for Surface 17:15
Frantic February Schedule 30:40
Projecting Kasatkina and Ostapenko 38:30
Svitolina Future #1? 43:53
Pressure of Serving for the Match 51:30
Tiafoe Breakthrough 55:53
One-Dimensional Serve Players 1:03:20

Dominic Thiem, Old-School Clay Court Specialist

Italian translation at settesei.it

With a tennis calendar tilted heavily toward hard court events, we don’t see many true clay court specialists these days. The best male players who excel on clay are forced to adapt their games to hard courts, as well: Rafael Nadal has won six majors off of clay, while Pablo Carreno Busta and Diego Schwartzman have both hoisted trophies at tour level hard court events. It’s possible to play a mostly-clay schedule at the Challenger level, but it’s nearly impossible to establish yourself as an ATP regular without winning some matches on hard courts.

Dominic Thiem is capable enough on fast surfaces, but more than any other tour player, he is considerably better on the dirt than off it. In the last 52 weeks, he has won 25 of 31 matches on clay, compared to only 24 of 42 on other surfaces. Against the top ten, he is a respectable 7-9 on clay (more impressive when you consider that 12 of the 16 matches were against the Big Four, seven of them facing Nadal, and two of the others came against Stan Wawrinka), but a dismal 2-15 on hard courts. If you, like me, had settled into thinking of Thiem as a solid but not particuarly threatening member of the top ten, you probably didn’t realize quite how bad he is on hard courts–or just how good he has become on clay.

When only clay court results are taken into consideration, Thiem rates as the second-best player on the surface. According to clay court Elo, the Austrian outranks everyone on tour except for Rafa and Novak Djokovic, whose rating reflects his skill level when he last regularly played and very likely will overstate his ability when he returns. Thiem trails Nadal by about 180 points, 2410 to 2235, implying that in a head-to-head matchup, we’d except the Austrian to win only 26% of the time. But when we compare Thiem to the rest of the pack and exclude the walking wounded–Djokovic, Wawrinka, Andy Murray, and Kei Nishikori–along with clay-skipper Roger Federer, his position looks much better. The next best clay courter, Alexander Zverev, trails Thiem by about the same margin, nearly 170 points.

A clay court Elo rating over 2200 is a useful marker of elite status. In the professional era, only 29 players have reached that level, 22 of whom can count at least one Grand Slam title to their names. Among active players, only the Big Four, Nishikori, Juan Martin del Potro, David Ferrer, and Thiem belong to the club.

Where Thiem really stands out is the juxtaposition of his clay court success and his hard court mediocrity. After his title last week in Buenos Aires, his Elo rating based only on clay court results was 2234, compared to a hard court rating of 1869. The first number, as we’ve seen, is good for third overall, second if we exclude Djokovic’s increasingly stale results; the second puts him 31st on tour, behind Schwartzman, Damir Dzumhur, and Fabio Fognini.

No one active today is more of a clay specialist–in the sense that his results on clay exceed his results on hard–than Thiem. (There are some even more extreme differences between grass and either hard or clay, but the brevity of the grass season means that many of those contrasts are due only to small samples.) The ratio of Thiem’s clay court Elo rating to his hard court rating–again, 2234 to 1869–is 1.20, far beyond any of the 44 other active players with a clay court Elo rating of 1800 or higher. Simone Bolelli comes in second, at 1.12, and a handful of players, including Nadal, register at 1.10. Here is the entire top 20:

Player                 Clay Elo  Hard Elo  Ratio
Dominic Thiem              2234      1869   1.20
Simone Bolelli             1834      1634   1.12
Rafael Nadal               2410      2182   1.10
Albert Ramos               1873      1696   1.10
Federico Delbonis          1869      1696   1.10
Pablo Carreno Busta        1921      1746   1.10
Pablo Cuevas               1873      1709   1.10
Nicolas Almagro            1903      1755   1.08
Karen Khachanov            1838      1701   1.08
Leonardo Mayer             1878      1741   1.08
Aljaz Bedene               1826      1695   1.08
David Ferrer               2017      1894   1.07
Philipp Kohlschreiber      1951      1845   1.06
Stan Wawrinka              2138      2027   1.06
Martin Klizan              1800      1709   1.05
Guido Pella                1825      1744   1.05
Borna Coric                1830      1760   1.04
Fernando Verdasco          1863      1794   1.04
Alexander Zverev           2067      1997   1.04
Feliciano Lopez            1830      1772   1.03

A few decades ago, when it was possible for top players to spend more than two or three months per year racking up points on clay courts, such lopsided ratings were a bit more common. Of the 29 men who have ever topped 2200 in clay court Elo rating, 11 have at some point recorded a ratio of 1.20 or higher. That includes Nadal, whose clay rating was 20% higher than his hard court number early in 2008, and Sergi Bruguera, whose ratio topped out at 1.29. Four other major titlists–Bjorn Borg, Juan Carlos Ferrero, Thomas Muster, and Guillermo Vilas–also exceeded 1.20 at some point during their career. To put Thiem’s specialization in context, though, consider that Guillermo Coria maxed out at 1.19 and Gustavo Kuerten peaked at 1.16. Even Ferrer–the epitome of the clay court specialist to a generation of fans–never exceeded 1.15 once his clay court Elo rating had passed the 2000-point threshold.

The category into which Thiem fits most neatly–specialists who are decidedly middle-of-the-pack on hard courts–largely belongs to an earlier era. When we lower our clay court Elo standard to a career peak of 2000 points, a mark equal to about 15th on tour right now, we’re left with a group of 145 players in the professional era. Of those, 65 (45%) were at some point as lopsided as Thiem is now, with a clay-to-hard rating ratio of at least 1.20. Yet only five of those belong to active players (Nadal, Thiem, Fognini, Pablo Cuevas, and Nicolas Almagro) and two-thirds of them came before 1995.

In some cases, players with substantially better clay court results learn to compete at a higher level on faster surfaces. Thiem is 24, and Nadal had a similar specialist’s ratio at age 22. Other former greats enjoyed early success on clay and quickly figured out hard courts as well. The Austrian may prove to be a late bloomer in that regard. That’s unlikely, but when Nadal retires or (improbable as it seems) fades, Thiem is poised to rack up titles and emerge as the greatest clay court player of his generation, regardless of whether his hard court game improves.

Podcast Episode 19: Comeback Stories

Episode 19 of the Tennis Abstract Podcast, with Carl Bialik, covers a slew of comeback stories, from Federer’s return to No. 1 to Kei Nishikori and the inaugural New York Open, with more than a glancing mention of Maria Sharapova’s progress and the impending appearances on tour of Serena Williams and Marion Bartoli.

Thanks for listening!

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

Update: Thanks to FBITennis, here are timestamps and an outline of this episode:

Theme: Comebacks 0:38
Federer Comeback 1:15
Fed’s Ability to Retain #1 5:37
Long Island ATP 250 (NY Return) 19:33
Nishikori Comeback 25:23
Bartoli Unretirement 35:15
Sharapova Comeback Progress 41:45
Serena’s Anticipated Comeback 48:04
Crazy Aussie Open Results 55:00
Mining the Challengers 1:03:48
WTA Consistency in Top 10 1:06:28

Roger Federer’s 20th, Easiest Grand Slam Title

Italian translation at settesei.it

After Rafael Nadal’s US Open title last fall, I wrote a piece for the Economist that attempted to measure each Grand Slam title by difficulty. If you’re interested in the methodology, you can review it there. The conclusion was intriguing: Nadal’s opponents en route to his 16 major titles were considerably more difficult than the routes Roger Federer took to his first 19. By “difficulty-adjusted” Slam titles, Rafa led by a whisker, 18.8 to 18.7.

Since then, Federer won the 2018 Australian Open, incrementing his major tally by one. Even though he faced rather weak competition, surely the additional title nudged his difficulty-adjusted total above Rafa’s, right?

It did, but not by much. Adjusted for difficulty, Roger’s seven wins in Melbourne were worth only 0.42 majors. By comparison, his previous low was the 2006 Australian, worth 0.61, and Rafa’s lowest was last year’s US Open, at 0.62. Federer’s previous average was 0.98, Nadal’s was 1.18, and Rafa’s route to the 2013 French Open was worth a whopping 1.65.

Fed’s draw was historically weak. Only a handful of majors in the professional era were easier for their champion, and they all came before 1985–most of them in Melbourne, which didn’t yet attract the best talent in the world. This year’s Australian Open path to the title was even weaker when put in the context of the current decade: The average major title from 2010-17 was worth 1.23, largely because the Big Four usually needed to overcome each other.

According to surface-specific Elo, the toughest challenge Federer faced last month was Tomas Berdych, closely followed by Marin Cilic. Even after deep runs in Australia, neither player even ranks in the current Elo top ten. The algorithm that adjusts slam titles considers how the average major champion would fare against a particular set of competition; against Berdych and Cilic, that hypothetical average champ is expected to win 88% and 89% of the time, respectively. Even Nadal had to get past Juan Martin del Potro in New York last year.

Still, Federer can claim the top spot on yet another list, as his 19.1 difficulty-adjusted Grand Slam titles exceed Rafa’s 18.8 as well as the 15.3 of Novak Djokovic. It doesn’t have quite the same ring that “20 majors” does, and it’s in considerably more immediate danger. If Nadal stays healthy and wins the French Open, he is virtually guaranteed to reclaim the difficulty-adjusted crown, and by a wider margin than Roger currently holds. Roland Garros has traditionally been tough: With the exception of 2010, all of Rafa’s trophies in Paris have been tougher than average. Unlike the traditional Grand Slam tally, the difficulty-adjusted ranking could yo-yo between the two rivals for as long as they remain competitive.