Dayana Yastremska’s Erratic Attack

Also today: February 2, 1974

Power giveth, and power taketh away. Few women hit as hard as Dayana Yastremska does, and sometimes, when enough of her returns find the court, that translates into victory. She squeaked through Australian Open qualifying by winning three deciding sets against players outside the top 200, then demolished 7th seed Marketa Vondrousova and rode the resulting momentum all the way to the semi-finals.

Then, yesterday in Linz, she managed just two games against Donna Vekic. So it goes.

The Ukrainian is essentially Jelena Ostapenko lite, mixing a middling serve with monster groundstrokes and a do-or-die approach on return. I wrote a few weeks ago about how Ostapenko’s game style leaves her unusually susceptible to chance; that applies even more to her less accomplished colleague.

The good news for Yastremska is that momentum is temporary. She’ll have off days, like the 92-point flop against Vekic, and she’ll occasionally play a perfect hour, like the dismantling of Vondrousova. More often, though, she’ll pack it all into a single match. The 23-year-old’s stats from her third-round adventure in Melbourne against Emma Navarro make for a good illustration:

       SPW%  RPW%  Winners  UFE  
Set 1   64%   54%       12   11  
Set 2   50%   33%        6   15  
Set 3   73%   56%       15    8 

I’ll bet you can tell which sets she won. It was a lopsided match, just not always in favor of the same player.

Typically, the wildest fluctuation came in Yastremska’s return numbers. Her serve is a weak point–she holds less than 60% of service games, worse than all but one other top-50 player–and it is no picture of consistency, either. But her return is a shot she can ride to a major semi-final. In the first five matches of her Australian Open campaign, she won 48% of return points, including 21 of 38 break point chances. Against Victoria Azarenka in the fourth round, Yastremska landed only 60% of her returns, but when she put the serve back in play, she won nearly three-quarters of the time. Almost one in six Azarenka service points ended with a Yastremska return that Vika couldn’t handle.

A few days later against Qinwen Zheng, the same attack proved to be too risky. The Ukrainian put just half of Zheng’s serves back in play. More than 20% of those returns ended the point, but against all of the free points she gave away, it wasn’t enough. Unlike the scattershot second set of the Navarro match, there wasn’t enough time to find the range before the contest was over.

The streaky slugger

After Yastremska’s eight straight wins from qualifying to the Australian Open semi-final, it’s tempting to call her a streaky player. Combine the big-picture run with narrow-focus ups and downs like the three sets of the Navarro match, and she looks like a kite blown around by the winds of chance at both the macro and micro levels.

I normally dismiss claims that any player’s results are particularly momentum-driven: While athletes aren’t robots, study after study suggests that if momentum (or “clutch” or “streakiness”) is real, it’s a minor effect, far more minor than commentators or the casual fan seems to believe. But after watching the Ukrainian’s three sets against Navarro, I had to test it.

Here’s a more precise hypothesis: Yastremska is more likely to win a game when she has won the previous game, compared to when she has lost the previous game. That isn’t the whole story of in-match streakiness, but for a single number, I think it gets to the core of the issue.

Result? True!

Player                 Change after Gm-W  
Alison Riske Amritraj             +11.9%  
Linda Fruhvirtova                  +9.7%  
Lesia Tsurenko                     +8.9%  
Irina Camelia Begu                 +8.7%  
Ajla Tomljanovic                   +7.1%  
Kaja Juvan                         +6.5%  
Polona Hercog                      +6.0%  
Yulia Putintseva                   +5.6%  
Shuai Zhang                        +5.4%  
Dayana Yastremska                  +5.3% 
--- 
Jelena Ostapenko                   +3.2%  
Iga Swiatek                        +1.6%  
-- Average --                      +1.0%  
Aryna Sabalenka                    +0.3%  
Elena Rybakina                     -0.8%  
Coco Gauff                         -1.2%  
Caroline Garcia                    -3.3% 

Among the 102 women with at least 20 charted matches since 2017, Yastremska ranks in the top ten, winning games more than 5% more often than average when she has won the previous game. She out-momentums her fellow hyper-aggressor Ostapenko by a modest amount. Another slugger, Aryna Sabalenka, seems to be impervious to previous results, even more so than the slightly streaky average player.

(The exact metric compares games-that-follow-games-won to games-that-follow-games [that is, games that don’t begin a set] within the same match, and excludes tiebreaks. Winning a match 6-0 6-0 isn’t “streaky” by this measure, because it’s impossible to know whether the result is due to a lopsided matchup [or injury] or to momentum–the winner went 10 for 10 in games that followed games won, and 10 for 10 in games that followed any game. With this metric, a streaky player is one who wins 10 of 20 total games in a match including, say, 7 of 10 games that follow other games won.)

So Yastremska is a little tougher to beat when she’s on a roll. She’s really hard to derail if she has just won a game and you have the misfortune of serving. Here is the same metric, only limited to winning percentage in return games:

Player             After Service Hold  
Katerina Siniakova             +13.4%  
Dayana Yastremska              +13.3%  
Lauren Davis                   +13.0%  
Linda Fruhvirtova              +12.2%  
Tatjana Maria                  +11.2%  
Alison Riske Amritraj          +10.8%  
Marta Kostyuk                  +10.3%  
Anhelina Kalinina               +9.9%  
Yulia Putintseva                +9.6%  
Qinwen Zheng                    +8.8% 
--- 
Jelena Ostapenko                +2.7%  
Iga Swiatek                     +2.6%  
Aryna Sabalenka                 +2.2%  
-- Average --                   +1.0%  
Coco Gauff                      -1.3%  
Caroline Garcia                 -4.9%

Yastremska’s success in return games skyrockets after she has held serve. Maybe she feels especially confident after getting through a service game; maybe a hold is a sign that her whole game is clicking. Whatever the reason, she rides this particular type of momentum as much as anyone, trailing Siniakova at the top of the list by a meaningless 0.031 percentage points.

You might suspect–or at least, I initially suspected–that streakiness is related to slugging. It’s easy enough to invent a story to link the two: Big hitting is risky; winners and errors come in batches. But no, there’s virtually no correlation, positive or negative, between these measures of streakiness and any of the metrics I use to quantify aggression. Grinders like Yulia Putintseva share the top of the list with Yastremska, while attackers like Caroline Garcia appear at the other extreme.

For the Ukrainian, it seems, the ups and downs are here to stay. Until she gets more out of her serve, she’ll continue to get dragged into three-set battles against opponents much further down the ranking list. As long as she doesn’t miss too many returns, she’ll keep herself in position to win. The losses will sometimes be ugly, but the victories–like the games that contribute to them–will compensate by coming in batches.

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February 2, 1974: Five-dollar words

My favorite moments in early-1970s tennis came when Billie Jean King got feisty. I don’t mean the take-this-fight-to-Congress, crusading Billie Jean, though there was plenty of that. On the rare occasions when an opponent pushed Madame Superstar to the brink, she could get downright nasty. Pity the poor linesmen.

Fifty years ago today, King faced longtime friend, doubles partner, and punching bag Rosie Casals in the semi-finals of the Virginia Slims of Washington. It was the marquee match of the week, with all of the tour’s other stars absent. Chris Evert and Nancy Richey were taking the week off, Evonne Goolagong was chasing appearance fees on the other side of the globe, and Margaret Court was pregnant. Billie Jean took it upon herself to keep the crowds happy: She went to three sets in the opening round against Kerry Harris, then delivered a 6-0, 6-1 masterclass to win her quarter-final against the 17-year-old Kathy Kuykendall.

Some fans griped about the ticket prices: five bucks for the King-Casals semi and six dollars for the evening session, which featured Australians Kerry Melville and Helen Gourlay in the other semi-final. The 2,800 locals who showed up for the afternoon match, at least, got their money’s worth.

Casals rounded into form just in time, having struggled a bit to recalibrate her game as the tour seesawed between indoor and outdoor events. Her athletic net game outpaced King’s own attack throughout the first set, leading Billie Jean to find a scapegoat among the officials. She berated the service line judge, even threatening to quit; Casals had to calm her down and convince her to stay. (Rosie quipped later that she deserved 60% of the prize money for keeping her pal on court.) After the Old Lady vented her wrath at the chair and two separate linesmen, she settled for moving the offending service line judge to the net cord.

“What this game needs are professional linesmen,” King said. “We’re years behind the times. There are too many questionable situations for a bunch of amateurs to try to master. I’ve suffered through 21 years of bad line calls, and I’m fed up.”

Tennis officiating was certainly a mixed bag. A few months earlier, at the men’s season-ending Masters event in Boston, a last-minute strike forced organizers to pluck fans from the crowd to call the lines.

But not everyone believed that Billie Jean’s reaction was warranted, or that it was triggered by what King called her own “low boiling point.” Melville and Gourlay played their match with the same crew and had no problems. “Most of this arguing with linesmen is done for tactical reasons,” Melville said. “It helps intimidate them. You can get away with it over here, but not in Australia.”

The offending service line judge, Stew Saphier, had a few words of his own. Nothing like this had ever happened to him before, and he wasn’t embarrassed by it. Why not? “Because I was correct in all my calls.”

Whatever the cause of King’s outburst, the day ended as it usually did. After dropping a 7-5 first set to Casals, she came back to win, 6-2, 6-0. The next day, she dispatched Melville 6-0, 6-2, completing the rare feat of a tournament victory that included a 6-0 set won in every match. She was now 14-1 on the young season, her only loss coming in the previous week’s final against Evert. Past her 30th birthday, more famous than ever, she still had plenty of battles ahead.

* * *

Meanwhile, in Ohio…

The men competing at the 1974 Dayton Pro Tennis Classic didn’t draw much in the way of crowds, but tournament organizers slapped together a sure-fire attraction: an exhibition match between Bobby Riggs and Cincinnati Reds star Pete Rose. 4,000 fans turned out for the famous court hustler and baseball’s “Charlie Hustle.” It was clear what they came for: Half of them left before the next regulation match got started.

“This is a disgrace for tennis,” said Yugoslavian veteran Boro Jovanovic. “People don’t come out to see us all week, then they come out for something like this.”

Rose insisted that Riggs play him “straight,” but after three games of running the outfielder ragged with all the spin that a 55-year-old arm could muster, the clowning began. Riggs donned everything from baseball catcher’s gear to a dress, and he eventually set out beach chairs and carried a briefcase to further aid his opponent’s cause. Final score: five games to two, Riggs.

Bobby recognized that rematches with King and Court were off the table and that neither Evert nor Goolagong were likely to accept a challenge. “I’d like to play women from all the world,” he said, naming Casals as potential foe. In the meantime, he’d take on all comers. With his Battle-of-the-Sexes celebrity still going strong, he knew people would show up to watch.

Click here for other posts about the 1974 season. Or here for dispatches from 1924.

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