Pablo Carreno Busta, of Spain, serves to Tennys Sandgren, of the United States, during the tennis competition at the 2020 Summer Olympics, Saturday, July 24, 2021, in Tokyo, Japan. (AP Photo/Patrick Semansky)

Pablo Carreno Busta, of Spain, reacts during a tennis match against Tennys Sandgren, of the United States, at the 2020 Summer Olympics, Saturday, July 24, 2021, in Tokyo, Japan. (AP Photo/Patrick Semansky)

Tennys Sandgren, of the United States, returns to Pablo Carreno Busta, of Spain, during a tennis match against at the 2020 Summer Olympics, Saturday, July 24, 2021, in Tokyo, Japan. (AP Photo/Patrick Semansky)