Aslan Karatsev, of the Russian Olympic Committee, returns to Tommy Paul, of the United States, during the tennis competition at the 2020 Summer Olympics, Saturday, July 24, 2021, in Tokyo, Japan. (AP Photo/Patrick Semansky)

Aslan Karatsev, of the Russian Olympic Committee, returns to Tommy Paul, of the United States, during the tennis competition at the 2020 Summer Olympics, Saturday, July 24, 2021, in Tokyo, Japan. (AP Photo/Patrick Semansky)