Coco Gauff fired an Australian Open warning shot as she swept aside former champion and fellow American Sofia Kenin, while Stefanos Tsitsipas became the first big name to fall at the tournament on Day 2 at Melbourne Park on Monday.

Gauff, the world No. 3, who is unbeaten this year after leading the U.S. to victory in the United Cup, eased past the 2020 champion 6-3, 6-3 in 80 minutes.

"I knew it was going to be difficult, but you know, I'm happy with how I played," said Gauff, the 2023 U.S. Open champion who admitted to being troubled by the fierce Melbourne sunshine when serving.