The first edition of the new U.S. Open mixed doubles tennis tournament has its final field — at least for a day or two. After announcing 14 teams late last month, the United States Tennis Association (USTA) has given the last two wild card spots to Naomi Osaka and Gael Monfils, and Jannik Sinner and Kateřina Siniaková.

The world’s top-ranked men’s singles player has ended up with one of the world’s best doubles players — who is also a multiple Grand Slam winner and Olympic champion —  immediately placing them among the favorites to win the $1 million first prize.

Both the direct-entry field and the wild-card entries had last-minute changes.

Sinner lost his original partner, Emma Navarro, who withdrew. When he ended up with Siniakova, their combined singles ranking was not high enough to receive direct entry, so they needed a wild card.

Jasmine Paolini withdrew, and her previous partner, Lorenzo Musetti, re-paired with Caty McNally. They needed a wild card, too. But Frances Tiafoe and Madison Keys no longer needed one. So there was room for everyone, including Osaka and Monfils, and even Andrey Rublev and Karolina Muchova, who got in on direct entry.

2025 U.S. Open mixed doubles teams

Player 1Player 2Direct entryWild card

Jessica Pegula

Jack Draper

Iga Świątek

Casper Ruud

Elena Rybakina

Taylor Fritz

Amanda Anisimova

Holger Rune

Belinda Bencic

Alexander Zverev

Mirra Andreeva

Daniil Medvedev

Madison Keys

Frances Tiafoe

Karolina Muchová

Andrey Rublev

Emma Raducanu

Carlos Alcaraz

Olga Danilović

Novak Djokovic

Kateřina Siniaková

Jannik Sinner

Taylor Townsend

Ben Shelton

Sara Errani

Andrea Vavassori

Venus Williams

Reilly Opelka

Naomi Osaka

Gael Monfils

Caty McNally

Lorenzo Musetti

World No. 2 Coco Gauff is missing due to scheduling commitments, while world No. 1 Aryna Sabalenka is opting out, too.

The draw is filled with enticing first-round matchups, with Alcaraz and Raducanu facing Pegula and Draper and Świątek and Ruud facing Keys and Tiafoe, to name just two.

The tournament begins Aug. 19, the day after the Cincinnati Open singles finals, and concludes Aug. 20. The winning team will receive $1 million.

Doubles players have criticized the USTA for devaluing a Grand Slam trophy by introducing a new format and holding the tournament in the same week as singles qualifying, rather than alongside the tournament proper. USTA executives have responded that not enough people were watching or even thinking about mixed doubles. Nothing, they argue, devalues an event more than that.

So out went the 32-team tournament played alongside the singles events. In came first-to-four-games sets, with no-ad scoring and a match tiebreak at a set apiece, with ESPN interviewing players between the sets. The business will get done well ahead of the singles, giving players a competitive warm-up and the broader tournament a promotional boost, or so the theory goes. The start of the U.S. Open proper on Aug. 24 should not take anyone by surprise.

But the biggest question — whether all the players who raised their hands to play will actually play — remains an unknown. The biggest complication might be the singles finals of the Cincinnati Open, which will take place on Monday, Aug. 18, the day before the mixed doubles start. Alcaraz, Sinner, Świątek and Paolini are all playing that day, leaving no turnaround time.

The USTA will have a few teams in reserve as injuries and scheduling conflicts arise. Maybe the actual doubles players of renown, people like Marcelo Arévalo, who had offered himself up with Siniaková, before she grabbed the chance to play with Sinner, will enter the mix. Or Desirae Krawczyk and Evan King, or Hsieh Su-wei and Jan Zieliński. $1 million is $1 million after all, and the actual doubles players think they have a built-in advantage against even the top singles stars.

Olympic results from last year go some way toward proving that point: Rajeev Ram and Austin Krajicek eliminated the feted Rafael Nadal / Alcaraz partnership with a clinic in court geometry and rally tolerance at the net. But the loudly unspoken priorities of this new event — selling tickets and thrilling fans with an extra chance to see the biggest stars in the sport — have been met by this all-singing, all-dancing cast. The question is how many of them will make it from the poster to the stage.

(Photo of Jannik Sinner: Dylan Buell / Getty Images)