Why U.S. tennis player Cori 'Coco' Gauff, 15, is the talk of Wimbledon

What they're saying: "Gauff’s win showed remarkable mental toughness by a player who isn’t old enough to vote. She never cracked," the Washington Post said of her win against Hercog, 3-6, 7-6 (9-7), 7-5.

Flashback: At 13, Gauff was the youngest player to reach the 2017 U.S. Open girls’ final, losing to 16-year-old Amanda Anisimova. A year later, she won the French Open girls' singles title.

Why you'll hear about her again: Because of her age, Gauff can only play 8 professional tournaments annually. She's the only player in the women's main draw at Wimbledon playing under that restriction.

What's next: On Monday, Gauff goes up against her first seeded opponent: Simona Halep, the No. 7 seed and 2018's French Open winner.