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.

Venus Williams and Reilly Opelka take on Karolina Muchova and Andrey Rublev at 12:30 p.m. ET today, Aug. 19. The first day of the US Open Mixed Doubles tournament is airing on the ESPN+ streaming service. Right now, ESPN+ costs $11.99/month for new subscribers.

The thought of the top men’s and women’s singles players teaming up is one that has often intrigued tennis fans around the world.

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

Emma Raducanu and Carlos Alcaraz’s all-star partnership was brought to a premature end as they were beaten in the first round of the revamped US Open mixed doubles.

Jack Draper and Jessica Pegula cruised to a straight-sets win against Carlos Alcaraz and Emma Raducanu in the first round of the revamped US Open mixed doubles.

Veteran doubles experience overcame singles stardom as defending champions Andrea Vavassori and Sara Errani reached the semi-finals at the U.S. Open's reimagined mixed doubles on Tuesday, as the event kicked off with a new format and new fans.

Emma Raducanu and Carlos Alcaraz might have lost in the revamped US Open mixed doubles - but they win the hearts of the New York crowd.