World number one and defending champion Iga Swiatek took just 51 minutes to reach the French Open fourth round on Saturday as Coco Gauff ended 16-year-old Mirra Andreeva's memorable Paris debut.

Swiatek blitzed 80th-ranked Wang Xinyu of China 6-0, 6-0 on the back of 21 winners as the 22-year-old Pole took another step closer to becoming the first woman since Justine Henin in 2007 to win back-to-back titles at Roland Garros.

Of the six sets she has played so far, four have been to love. In all she has dropped just eight games through three rounds.

"It was a really solid performance from me. It's not easy to stay disciplined and keep your focus," said Swiatek.

"I took care of everything and I'm pretty happy with my performance."

Swiatek, who also won the title in 2020 and is targeting a fourth Grand Slam triumph, will face either 2019 US Open champion Bianca Andreescu or Ukraine's Lesia Tsurenko for a quarter-final berth.

Her path to the final was made easier earlier Saturday by the withdrawal of Wimbledon champion Elena Rybakina, a possible last-four opponent, due to illness.

Rybakina had been due to face Sara Sorribes Tormo of Spain in the third round in the opening match on Court Philippe Chatrier but said she was suffering with a fever.

Rybakina withdraws

"I was not feeling good yesterday and the day before. I didn't sleep last night," said the 23-year-old Kazakh.

"I had fever and a headache and it's difficult to breathe. I tried to play in the warm-up but I feel it's the right decision to withdraw."

Sorribes Tormo, ranked 132 in the world, will be playing in the second week of a Grand Slam for the first time. She will face either Ekaterina Alexandrova of Russia or Brazil's Beatriz Haddad Maia for a place in the quarter-finals.

World number six Gauff, the runner-up to Swiatek last year, came back from a set down to defeat Andreeva 6-7 (5/7), 6-1, 6-1.

Andreeva, ranked a lowly 143, had come through qualifying and was the youngest player to make the third round since 2005.

"Mirra is super young and has a big future," said Gauff. "I remember I played here when I was 16 so she has a lot to look forward to. I'm sure you'll see a lot more matches between us."

Gauff said that despite her first set problems, she was confident she could pull through.

"I was a little undisciplined in the tiebreak but I knew what the game plan was so I just tried to execute that in the second and third sets."

Gauff, 19, will face either fellow American Kayla Day or Anna Karolina Schmiedlova of Slovakia for a place in the quarter-finals.

Despite pocketing the first set, Andreeva collected a code violation for petulantly swiping a ball into the Court Suzanne Lenglen crowd.

Casper Ruud, the runner-up to Rafael Nadal in 2022, dropped the first set before easing to a 4-6, 6-4, 6-1, 6-4 win against China's Zhang Zhizhen.

The 26-year-old Zhang was bidding to become the first Chinese man since 1936 to reach the fourth round in Paris.

"It was very tough in the first set, he was hitting many winners and I couldn't find a hole in his game," said fourth-ranked Ruud.

"At 5-4 in the second set, he played some sloppy shots and that gave me the set, maybe the match," said Ruud who hit 36 winners and saved seven of 10 break points.

Ruud, Rune through

Ruud will next face in-form Nicolas Jarry after the Chilean edged out Marcos Giron of the United States 6-2, 6-3, 6-7 (7/9), 6-3.

Jarry had arrived in Paris with the Geneva clay court title under his belt and will be making a maiden appearance in the last 16 of a major.

Also featuring in the second week for the first time will be 49th-ranked Tomas Martin Etcheverry of Argentina who stunned 15th seed Borna Coric 6-3, 7-6 (7/5), 6-2.

Etcheverry will next face Japanese 27th seed Yoshihito Nishioka who edged a dramatic five-set battle with qualifier Thiago Seyboth Wild to reach the fourth round for the first time.

Nishioka battled back to win 3-6, 7-6 (10/8), 2-6, 6-4, 6-0 against the Brazilian who had knocked out world number two Daniil Medvedev in the first round.

Danish world number six Holger Rune eased through, seeing off 231st-ranked Argentinian qualifier Genaro Alberto Olivieri 6-4, 6-1, 6-3.

The 20-year-old, who made the quarter-finals on his debut last year, next faces either American ninth seed Taylor Fritz or Argentina's Francisco Cerundolo.