Serena, Keys into Australian Open fourth round

Seven-time Australian Open champion Serena Williams defeated fast-rising 18-year-old Ukrainian Dayana Yastremska, 6-2, 6-1, in 67 minutes Saturday to reach the second week of the Australian Open and remain on track to win a record 24th Grand Slam title.

No. 16 seed Williams had the match firmly in hand from start to finish, crushing 20 winners, including eight aces, and winning 85 percent of points on her first serve.

"I haven't played a lot since [the US Open in] New York," Williams said, during her post-match press conference. "But it is what it is. I'm here. I've trained in the off-season. You know, at this point I'm here. I'm here to play tennis, do what I do best. I play tennis best, so that's what I'm here to do."

Williams, who is going for her eighth title in Melbourne this year, will face world No. 1 Simona Halep in the fourth round. Halep advanced Saturday by defeating Venus Williams, 6-2, 6-3.

No. 17 seed Madison Keys (pictured above) also advanced Saturday, posting a 6-3, 6-2 victory over No. 12 Elise Mertens of Belgium. The win was the American's third straight-sets victory of the tournament.

"I think I played really well today," Keys said. "I served well, especially in the first set, getting out of some break-point situations. I think she played really well, which just made me raise my level.

"In the second set, being able to break a couple of times and bounce back from being broken back, overall I'm just really happy with how everything went today."

Keys, a quarterfinalist at the Australian Open in 2018 and semifinalist in Melbourne in 2015, will next face No. 6 Elina Svitolina on Monday.

Day 7 action will feature four Americans in the Round of 16. No. 5 seed Sloane Stephens will play Anastasia Pavlyuchenkova; 17-year-old Amanda Anisimova will take on No. 8 Petra Kvitova; two-time NCAA singles champion Danielle Collins will square off against No. 2 Angelique Kerber; and Frances Tiafoe, the lone American man left in the draw, will face No. 20 Grigor Dimitrov.