Tennis is the only professional sport in the world in which the earnings of the top women’s players can nearly match those of the top men’s players—four of the seven tennis players who made more than $20 million from endorsements and prize money combined over the past 12 months are women.

But how do these superstars stack up when they share the court together? The 2025 U.S. Open’s mixed doubles tournament, featuring a new format, gave us a window into answering this question. This year, the USTA attempted to breathe life into a Grand Slam event that was often viewed as an afterthought by offering a $1 million cash prize, moving it to the week before the main draw and enlisting the top singles players to participate.

Sportico tallied the sample of all 1,180 points from the tournament, in which the world’s best men’s and women’s singles players hit and served to each other; from this, we can glean insights into the gender dynamics of mixed doubles.

First, it’s no surprise that the serving team won a higher percentage of points when men served to women, and a lower percentage when women served to men. Teams won 72% of service points with the former combination, but only 55% with the latter. “Guys serve a lot bigger, so it’s always helpful,” semifinalist Jessica Pegula said. “A little bit of a different strategy on my side because obviously girls don’t serve as big.”

The average male player in this year’s mixed doubles field stands more than 6-foot-3, whereas the average female player was under 5-foot-10. As a result, men tend to have faster serves on average, and women’s shorter wingspans limit their ability to return well-placed serves or serves with spin carrying the ball away from them. Indeed, 6-foot-5 Taylor Fritz aced 5-foot-5 Sara Errani on five of 12 first serves, and 6-foot-11 Reilly Opelka aced 5-foot-11 Karolina Muchová on five of 11 tries. Overall, men aced women on 13% of first serves in the event.

Somewhat counterintuitively, though, women serving to women won 63% of points, a tad higher than the 62% won by men serving to men. This is surprising considering that service hold percentage is higher in men’s doubles than women’s doubles and in men’s singles as compared to women’s singles. The women also aced each other less than the men aced each other (3% of first serves vs. 5%).

The gender of the net player, though, makes a big difference in mixed doubles. When women serve, their male partner may have a longer reach at the net to poach and put away mediocre returns, whereas when men serve to men, their female partner at the net likely has less range to finish points on the second shot with a volley.

This importance of the net player was salient when watching the eventual champions, doubles specialists Errani and Andrea Vavassori. Errani had the slowest serve in the tournament, but the team won 63% of points on her serve, and an even higher 65% when she served to men (22 out of 34).

“[Vavassori] moves so well at the net. Singles players don’t think about [a net player] crossing when someone serves at 70 miles an hour,” runner-up Casper Ruud said. “You feel like you hit a good return, but he’s there, and he puts away a volley.”

Errani’s success in the tournament also demonstrates that there’s more to serving than pure velocity, especially in doubles. “[Her serve] is not apparently strong if you’re looking at the miles per hour, but she has good placement on the serve… a lot of topspin, a lot of slice, and she mixes her targets well,” semifinalist Danielle Collins said. “It’s tricky, for a lot of the guys especially, because the guys don’t see that type of serve very often.”

Despite some statistical differences, the full picture painted by the data shows that women more than hold their own on the court, as they still won the majority of points when serving to their male peers. “There’s not much difference,” Pegula said of her experience between playing mixed doubles versus women’s doubles.

In the early rounds of the tournament, there were even two instances of a woman acing a man, including 45-year-old Venus Williams rocketing one past 27-year-old Andrey Rublev at 105 miles per hour and earning a roar from the crowd.