ATP Single-Country Finals in the Open Era

Today’s Washington final between Milos Raonic and Vasek Pospisil is the first all-Canadian final in the Open era. Here’s a list of the other 20 countries that have represented both sides of an ATP final, along with the total number of such finals and the most recent such match:

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Donald Young’s Perpetual Hopes and the Lefty Serve That Isn’t

Donald Young celebrated his 25th birthday last week, and if you’ve been following the ATP for any part of the last decade, you know all about his talent, his potential, and his underwhelming results. Every time he goes deep in a tournament–as he has in Washington this week, upsetting Kevin Anderson in three sets today–all that upside talk gets dredged up again.  Is this finally the breakthrough for which we’ve waited so long?

In general, it’s a safe bet to watch longer-term trends more closely than short-term peaks and valleys. So the short, obvious answer is: No, it’s unlikely to be a sign of much greater things to come. Still, Young has beaten three top-50 players this week, and it’s a good time to take a closer look at what might be holding him back.

A prime obstacle isn’t hard to identify. Donald has one of the weakest serves on the ATP tour. While that doesn’t automatically keep him out of the top fifty in the world, it sure doesn’t help. Young’s year-to-date ace percentage, 3.4%, is among the ten worst on tour, and with the exception of David Ferrer and Roberto Bautista Agut, none of the other players on that list are inside the top 35. This year’s number is no slump, as Young’s ace rate has been below 4% every year since 2009.

Another metric to indicate the effectiveness of a player’s service game is the ratio of service winning percentage to return winning percentage (SW/RW). If a player wins lots of service points, it might be due to a good serve, or it might owe to a strong overall game. This ratio gives us a rough measure of how much a player’s success on serve is due to the serve itself.

Coming into Washington this week, Young’s SW/RW was 1.49, one of the lowest marks of any left-handed tour regular in the last ten years. A few right-handers succeed while winning only 50% more service points than return points–including Ferrer and, for one season, Andy Murray–but the average player on tour wins roughly 73% more serve points than return points. Even Rafael Nadal hasn’t fallen below the 1.5 mark since 2005.

As Ferrer has demonstrated, a player with Young’s level of service success can have a very good career on tour. Yet Ferrer’s skillset is unusual, and importantly, he’s a righty.

Not every successful ATP left-hander is a big server. Nadal won dozens of titles before fully developing the serve he uses today. Neither Fernando Verdasco nor Jurgen Melzer, two lefties who cracked the top ten, are known for overpowering deliveries. But in the last decade, Nadal is the only left-hander to consistently succeed with a SW/RW under 1.6.

It’s a different story for righties. As we’ve seen, Ferrer is a perennial top player despite Young-like serve stats. Fabio Fognini, Nikolay Davydenko, and Lleyton Hewitt have all enjoyed solid seasons without greater serve dominance than Young. (Though Hewitt has racked up better ace totals.)

Surprisingly, it isn’t that lefties are bigger servers. On average, both lefties and righties win about 73% more service points than return points. The tentative conclusion I see from these numbers is that lefties–with the typical exception of Rafa–can’t get away with a weak serve the way that right-handers can.

Young’s SW/RW this week of 1.69 suggests that, despite only 13 aces in four matches, he’s playing well behind his serve, and the results have followed.  It may be, though, that a modest improvement to his serve–or perhaps his tactics behind the serve–would be particularly valuable, seizing whatever specific advantages worked for guys like Verdasco and Melzer.

If Young is (finally) to take a big step forward, he’ll need to do more with his serve for a season–not just a week. He doesn’t need to become the next Feliciano Lopez; he just needs to be a little less like a left-handed Fognini.


Filed under American tennis, Serve statistics, Washington

Serve-and-Pray: The Quirks of Isner’s Early Exit

The big story after Steve Johnson‘s upset of John Isner today was Isner’s unhappiness with his court assignment. Still, for those of us more interested in the game itself than in post-match carping, Johnson’s surprise victory was plenty notable.

Almost every Isner match is a serve-dominated, one-dimensional contest. This one was even more unidimensional than usual. Both players won 89% of first-serve points, a combined mark that stands as the most extreme of the season. Two players haven’t combined to win more than 89.2% of first serve points since Brisbane early last season, when Grigor Dimitrov and Milos Raonic combined for an outrageous 94.0% of first-serve points won.

The difference between Isner and Johnson–slim as it was–appears in their success rate on second-serve points. Johnson won an impressive 68% of second offerings, while Isner won only 43%. That typically doesn’t do the job–since 2010, Isner has won only eight of 36 matches when he wins fewer than 45% of second-serve points. Still, he managed to avoid clustering too many of those ineffective second serves, allowing Johnson only two break points.

As bad as that second-serve winning percentage is, it would often by sufficient when combined with that other-worldly win rate on first serves. Taken together, he won 73% of service points, which–barring particularly good or bad streaks–translates to a hold of serve in 93% of service games. That’s Isner’s hold rate for the season so far, and sure enough, it was his hold rate today, when he was broken only once in 16 tries.

While Big John often seems unbreakable, he typically loses a service game or two in every match–even on the days he wins. He’s been broken exactly once in nine hard-court matches this year, and he’s won seven of those matches.  Since 2010, he’s won 45 of the 60 matches in which his opponent broke him exactly one time–many of them thanks to his excellent tiebreak record.

But today, his opponent really was unbreakable. Compared to Johnson’s service numbers, Isner’s look positively pedestrian. Steve won 80% of service points, which–again, barring too much streakiness–translates to a hold of service in an incredible 97.8% of service games. Put another way, that’s one break of serve every eight sets or so.  (For reference, Isner’s 93% season-to-date average is best on tour, and no one topped 92% for the 2013 season.)

Johnson’s not usually that good–Isner’s indifferent return game explains much of the magnitude of these numbers. Still, it’s an extremely bad return performance by any standard. It’s only the fifth time since 2010 that Isner has won so few return points in a match he completed, and it’s only the second time this year he has failed to earn a single break point. Remarkably, that last aspect of return futility isn’t always enough to keep him out of the win column: Three times, he has won a tour-level match without earning any break points.

Today, despite the lack of break points, despite the dismal second-serve percentage, despite winning 12 fewer points than his opponent, he found himself in a third-set tiebreak, two points away from victory. Big John’s game isn’t much fun to watch–while this all transpired, I was across the grounds taking in a doubles match–but on paper, his results are endlessly fascinating.

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First Look: Francis Tiafoe

Last night at the Citi Open in Washington, Francis Tiafoe played his first tour-level main draw match. For a 16-year-old with almost no professional experience, he put on a good show, making Evgeny Donskoy work hard for his 6-4 6-4 victory.

Tiafoe is one of a few young American men viewed as rising stars. He doesn’t have the professional experience of Stefan Kozlov or Jared Donaldson, but he has nonetheless racked up some impressive feats in the last eight months, claiming the title at the Orange Bowl in December and another big win at the Easter Bowl in April.

His game, as viewers discovered last night, is a work in progress. He lit up the radar gun with both serves and forehands, but neither was steady enough to avoid getting broken by Donskoy three times. His backhand, the less showy but more consistent half of his ground game, was sufficiently solid to keep him in points, but it aside from a couple of down-the-line bullets, it was rarely enough to win them.

Both serve and forehand are, at this stage of his development, very complicated shots. His serve is a bit jerky, and his second serve is particularly erratic. A more offensive kick serve would do wonders for his service game–he won barely 40% of second-serve points yesterday.

The forehand is an even bigger problem. It’s easy to get fooled by the occasional big winner–he did hit some sensational shots from that wing last night. The bigger picture, though, is that his big, not-very-fluid windup prevents him from hitting the effective rallying shots that are absolutely necessary to compete at this level. Compared to top-100 players, Donskoy is not a particularly tough test, and Tiafoe hit 19 unforced errors from that side alone. That’s 20% of his total forehands in the match–double the tour-average rate of forehand unforced errors. They also accounted for one-third of all the points he lost.

It could have been worse. Donskoy, whether because he feared the forehand or because he stuck with familiar patterns, tended to rally back to Tiafoe’s backhand. That shot is far smoother, simpler, and much, much more consistent. While he didn’t try for nearly as much off that wing, he did hit four winners–and only four unforced errors.

He tended to play far behind the baseline, so it was a rare point that displayed other aspects of his game. In the second set, he opted for a few more slice backhands, a shot he seemed to have a decent feel for. He hit one very slick backhand drop shot for a winner, but more often when he ventured inside the baseline, he didn’t appear to have a natural sense for smart, reasonably-high-percentage plays.

It’s important to keep all this in perspective, though. Tiafoe is the youngest man to play an ATP main-draw match this year–nine months younger than Alexander Zverev, for instance. Donskoy was his first top-300 opponent and last night was only his 15th professional match. If he didn’t look particularly poised rushing between points, I think we can let it slide.

As strong a player as Tiafoe is for his age, the inconsistency of both serve and forehand will likely keep him out of the spotlight for another few years. Unlike Zverev and Borna Coric, he won’t be challenging top-50 players before his 18th birthday. Still, there are a lot of good qualities to build on, and when he hits his twenties, he could well be part of the next great generation of American players on the ATP tour.

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Premier or International? Balancing Rewards and Draw Quality

This week, WTA players had a choice of tournaments: a Premier event in Stanford or an International in Washington. Stanford offers far more ranking points–470 to Washington’s 280 for the winner–and an even bigger difference in prize money–$120,000 to $43,000.

For the very best players, it’s an easy choice to head for the event with the biggest rewards. But further down the rankings, it’s not so clear cut. If enough top contenders gather at one tournament, there may be easier points (and dollars) for the taking elsewhere.

The pairing of Stanford and Washington provides a neat natural experiment that allows us to analyze players’ scheduling decisions. Both tournaments are in the same country and played on the same surface. The only major difference is the package of available rewards.

(Of course, for any particular player, there may be other strong reasons to choose one event or the other, such as local ties, previous success at the event, sponsorship commitments, or appearance fees. Also, some players might opt for Washington because of its closer proximity–and lack of time zone changes–to upcoming events in Montreal, Cincinnati, and New York. For the purpose of this analysis, though, we’ll have to ignore personal considerations.)

Lucie’s choice

Let’s start with an example: Lucie Safarova. The 17th-ranked Czech is the top seed in Washington. Before the draw was released, a simple ranking-based projection would’ve given her a 14% chance of winning the title, making her the favorite. Had she entered Stanford, she would’ve been the 8th seed, and a similar forecast would’ve given her a 3% chance of winning the title.

Advantage Washington? If Lucie wants prestige, a trophy, and more time on court, yes. But if she prefers ranking points and cash, she still should have gone to California.

That 14% chance of winning the Citi Open title, combined with her pre-tournament odds of reaching each preceding round, gives Safarova a weighted forecast of 87 ranking points and $11,800 in prize money. Had she opted for Stanford, her weighted expectation would be 95 ranking points and $21,170.

Safarova’s comparison is indicative of what we find with many more players in action this week. Even with a higher chance of advancing to the final rounds in Washington, the ranking point balance tilts in Stanford’s favor, and the prize money difference is even more extreme.

California cash

The contrast between the two events is much starker in terms of dollars than in points. As we’ve seen, the champion in Stanford receives almost three times as much as her fellow trophy-winner in Washington, but not even twice as many ranking points.

Because the prize-money pot is so much bigger in Stanford, every direct-entry player in the draws of both tournaments would have expected a bigger check from Stanford. The differences run from the extreme–Agnieszka Radwanska could have expected only 38% as much prize money in Washington than in Stanford–to the less outrageous–Ekaterina Makarova, the Citi Open #2 seed, can expect 67% as much cash in DC as she would have expected in Stanford.

Still, every single player with the option to enter either event could have expected a bigger paycheck had they chosen Stanford.

Ranking point decisions

When it comes to WTA ranking points, Stanford holds much less of an edge. Of the 48 direct-entry players in the two tournaments, 11 of them can expect more ranking points in Washington than in Stanford, including Makarova, whose expected points haul is 15% greater in DC than it would’ve been at Bank of the West.  Most of the players who would’ve done better in Washington would be seeded in DC but not in Stanford, giving them the likelihood of a much easier early-round draw at the east-coast event.

Still, for the majority of players, the bigger rewards in Stanford outweigh the difficulty of the competition. 37 of the 48 direct entries would be expected to earn more points in Stanford, and for 15 of them, their expected points in Washington would be less than 80% as much as the comparable number in California. Nine of those 15 are playing Washington. In fairness, a few of those players were ranked below the cut for Stanford, so they didn’t have a choice.

On average, players in action this week could expect 15% more ranking points in Stanford than in Washington, along with double the prize money.

Smart choices

Not every player is going to maximize her chances of winning money and racking up points every week. But it does seem extreme that, given the choices that players made this week, the balance between risks (crashing out early to a great player) and rewards (points and cash) seems so out of whack.

It may be that secondary concerns, like proximity to other events, hold more importance that I am giving them credit for. It could be that, in the run-up to higher-stakes events next month, some players are interested in playing more matches. The Citi Open does offer the likelihood of that.  Also, some players commit to one event or the other before knowing much about the relative field strength–there is the possibility that players underestimated the quality of this year’s Washington draw, which has not always been so strong.

Still, it is striking to find little evidence that players made optimal choices. On average, the players who chose Stanford could expect 16% more ranking points than if they had played Washington. The players who opted for DC could have expected 14% more ranking points in Stanford–basically the same as their colleagues on the other coast.

With this much at stake, many players could’ve improved their lot simply by thinking through their options a little better. In general, if you’re likely to be seeded at one tournament and not the other, go where the seed is. If you will be seeded at both or unseeded at both, go where the higher stakes are.

For more detail on methodology, keep reading.

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Event History Pages at Tennis Abstract

If you like tennis records and trivia, you’d better clear your calendar. I knew I was on to something when I kept getting distracted from my own project by all the cool stats it was spitting out.

The project: Event history pages at Think of them as almanacs for every stop on the ATP tour. For each tournament, you’ll find a chronological list of winners, finalists, and final scores. Then come the leaderboards–132 of them per tournament, at last count. That’s where the fun really begins.

In addition to the basics, like most matches won, most quarterfinal appearances, and the like, you’ll find tiebreak records, bagel records, the youngest titlists (and finalists, and more), the oldest titlists (and finalists, and more), and the lowest ranked titlists, finalists, and semifinalists.

Then come the match-level stats records (all links head to the Washington event’s page as an example). These are broken down into four categories:

  • Single-match records (combined): Longest and shortest matches, most aces, most breaks of serve, longest tiebreaks, and much more.
  • Single-match player records: Most aces by a single player, highest and lowest first-serve percentage, highest and lowest first-serve winning percentage, most break points earned and saved, and lots more.
  • Single-tournament player records: Marks set by players at a single year’s event, including most time spent on court, most points won, highest rate of points won, aces, double faults … you get the idea.
  • Event player records: Best all-time performances at the tournament over multiple years, including most of the same stat categories from the other sections.

Player names are linked to each guy’s own page, and years are linked to a page with each individual tournament’s results.

The links above all go to the Washington tournament’s page. Here are links to this week’s ATP events:

(I’d love to have equivalent WTA pages, and I hope to add them soon. It’ll take quite a bit more work, however, and without the 24-year history of matchstats that is available for ATP events, the resulting pages will be much less thorough.)

While I’ve put a ton of work into these this week, you’ll still probably some bugs. That’s one of the downsides of leaderboards–they have a knack for uncovering mistakes in the database. I’ve been able to add several checks to the process to avoid matches with obviously incorrect stats (e.g. impossibly short match durations), but I’m sure we’ll keep discovering more.



Filed under History, Tennis Abstract

Margin of Error Podcast: Episode 24

A new podcast is out!

Amy and I cover Bernard Tomic’s surprise title in Bogota, Alexander Zverev’s and Ana Konjuh’s teenage exploits in Hamburg and Istanbul, and Viktor Troicki’s controversial wild card in Gstaad.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.


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