Novak Djokovic, of Serbia, returns a shot to Pablo Carreno Busta, of Spain, during the fourth r …

Novak Djokovic, of Serbia, returns a shot to Pablo Carreno Busta, of Spain, during the fourth r ...

Novak Djokovic, of Serbia, returns a shot to Pablo Carreno Busta, of Spain, during the fourth round of the US Open tennis championships, Sunday, Sept. 6, 2020, in New York. (AP Photo/Seth Wenig)