MELBOURNE, Australia (AP) — The only women's match featuring Grand Slam singles champions in the third round at the Australian Open turned out to be an overpowering win by Iga Swiatek over Emma Raducanu on Saturday.

Swiatek won the final 11 games of the match to beat 2021 U.S. Open champion Raducanu 6-1, 6-0 and become the first player through to the fourth round.

The No. 2-ranked Swiatek, who agreed to accept a one-month suspension in a doping case late last year, has won the French Open four times and the U.S. Open in 2022. She is nearly halfway to a possible Australian title — her best result here has been a semifinal appearance in 2022, losing to eventual runner-up Danielle Collins.

“I hit a few shots and afterwards I thought, ‘This is what I practice for.’ From the beginning I felt like I was playing well," said Swiatek, who won 59 points and lost 29 in the match. “I felt pretty confident, so at the end I could push for even more.”

Eighth-seeded Emma Navarro is also into the fourth round after beating Ons Jabeur 6-4, 3-6, 6-4. Navarro has now played in 30 three-set matches at WTA level since the start of 2024, the most of any player over that span.

Meanwhile, Alex Michelson joked that he was too busy at the Australian Open on Saturday morning to have a lengthy phone conversation with his mother back home in California. His excuse was pretty good, actually: The 20-year-old Michelsen was on court for a 6-3, 7-6 (5), 6-2 victory over No. 19 seed Karen Khachanov.

That victory put Michelsen in the fourth round at a Grand Slam tournament for the first time — and was his second win in less than a week over an opponent ranked in the top 20. He eliminated No. 11 Stefanos Tsitsipas in four sets in the opening round.

“Mom, hi! I'm sorry I only called you for a minute this morning. I had things to do,” the 42nd-ranked Michelsen said, looking into a TV camera during his post-match interview at John Cain Arena. “I love you. I miss you. I hope everything’s good at home.”

He'll now face either No. 8 Alex de Minaur of Australia or No. 31 Francisco Cerúndolo of Argentina for a berth in the quarterfinals.

“I'm going to sit back on the couch and watch tonight and see what happens,” Michelsen said.

He is the second-youngest man from the United States since Andy Roddick in 2003 to get this far at the Australian Open — two years ago, Ben Shelton was about 1 1/2 months younger than Michelsen is now.

Michelsen is part of a crop of Americans making moves in the brackets at Melbourne Park. Six U.S. men and five women from the country reached the third round — both tournament highs.

And Michelsen has done it by defeating two players with some real success at the hard-court event in the past: Tsitsipas was the runner-up in Australia in 2023; Khachanov lost to him in the semifinals that year.

Michelsen, who is coached by 2005 U.S. Open semifinalist Robby Ginepri, converted all four break points he earned against the big-serving Khachanov and compiled an impressive 39 winners to 27 unforced errors.

“I played unbelievable most of that match. I don't know what's going on. ... I’ve never hit my forehand that well,” Michelsen said. “Played some of my best tennis at the end.”