Semi-finals order of play today, pairings and prize money - Tennis’ biggest names will compete in a brand new format at the year’s final Grand Slam

Big names fell early and unexpected teams broke through to steal the spotlight on Day 1 of U.S. Open mixed doubles play, headlining an electric opener packed with upsets and standout performances.

The new event wanted to use singles stars to put mixed doubles on a pedestal. Two masters of the discipline have stolen the show.

Carlos Alcaraz and Emma Raducanu face off against Jessica Pegula and Jack Draper in the Mixed Doubles first round today, Aug. 19, at 2 p.m. ET. The first day of the US Open Mixed Doubles tournament is airing on the ESPN+ streaming service.

Jannik Sinner has withdrawn from the U.S. Open mixed doubles event, where he was going to partner Katerina Siniakova, a day after illness forced the world number one to retire five games into his Cincinnati Open final.

Following her 7-5, 6-4 final win over Jasmine Paolini to earn her first Cincinnati Open title on Monday night, the world No. 2 took a private jet along with Carlos Alcaraz to New York to arrive in time for the U.S. Open mixed doubles tournament Tuesday.

The No. 1-ranked Sinner, the defending champion in singles at Flushing Meadows, was supposed to compete in mixed doubles with Katerina Siniakova.