The Spaniard predicts big things for Coco Gauff, but says she should take her time.
The Canadian snagged her first main draw win at the US Open on Day 2, and bigger things could be coming.
Two-time Grand Slam champion suffers second straight first-round major exit.
"This chair umpire, I don't know, he has something against me," Stefanos Tsitsipas charged after his US Open first-round exit.
The Russian talks about his big win over Novak Djokovic and the aggression that played a role
The Canadian is already focussing on getting better for 2020.
The Swiss earned his spot in the second round by defeating Sumit Nagal in four sets.