Jack Draper, right, of United States, bumps firsts with Jessica Pegula, of United States, during their mixed doubles match at the U.S. Open tennis championships in New York.

Jack Draper, of United States, returns a shot during a mixed doubles match at the U.S. Open tennis championships, in New York.

Jack Draper, right, of United States, plays a shot as partner Jessica Pegula, of United States, covers during their mixed doubles match at the U.S. Open tennis championships in New York.

Carlos Alcaraz, right, of Spain, and Emma Raducanu, of Great Britain, react during their mixed doubles match at the U.S. Open tennis championships, in New York.

Carlos Alcaraz, right, of Spain, plays a shot as partner Emma Raducanu, of Great Britain, covers during their mixed doubles match at the U.S. Open tennis championships in New York.

Carlos Alcaraz, left, of Spain, and Emma Raducanu, of Great Britain, celebrate during their mixed doubles match at the U.S. Open tennis championships in New York.

Jack Draper, right, of United States, plays as shot as partner Jessica Pegula, left, of United States, covers during a mixed doubles match at the U.S. Open tennis championships in New York.

Emma Raducanu, of Great Britain, returns a shot during a mixed doubles match at the U.S. Open tennis championships in New York.

Novak Djokovic, left, of Serbia, and Olga Danilovic, right, of Serbia, interact during their mixed doubles match at the U.S. Open tennis championships, in New York.

Daniil Medvedev, right, and Mirra Andreeva react during mixed doubles match at the U.S. Open tennis championships in New York.

Novak Djokovic, right, of Serbia, and Olga Danilovic, left, of Serbia, talk during a break in their mixed doubles match at the U.S. Open tennis championships, in New York.

Daniil Medvedev, left, and his partner Mirra Andreeva react during a mixed doubles match at the U.S. Open tennis championships in New York.