“I kind of kept telling myself, ‘Just try to get the next point,’” Keys said, after clinching a 5-7, 6-1, 7-6 (8) victory.

Don't miss: Madison Keys' shot called in and out—and Frances Tiafoe's exchange with 'Young Sparky.'

Tennis continues to thrive, as 10 of the 15 athletes are WTA Tour players.