Tsitsipas shows win over Federer no fluke

"I mean, I feel a bit emotional but not too much because I know I worked hard to get here."

Seated in his courtside guest box were his parents and two siblings, along with Patrick Mouratoglou, who is Serena Williams' coach and serves as a mentor to Tsitsipas.

Now they'll turn their attention to his next opponent, either 17-time major champion Rafael Nadal or another up-and-coming member of the sport's new generation, 21-year-old American Frances Tiafoe.