PARIS, France (AFP) — World No. 1 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, who also won the title in 2020.

Swiatek will face Ukraine's Lesia Tsurenko, who breezed past 2019 US Open champion Bianca Andreescu for the loss of just two games, 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 opening match on Court Philippe Chatrier but said she was suffering with a fever.

"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," said the 23-year-old Kazakh.

Sorribes Tormo, ranked 132 in the world, will face Beatriz Haddad Maia, the first Brazilian to make the last 16 in Paris since 1979, for a place in the last eight.

World No. 6 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 19-year-old Gauff who will face Anna Karolina Schmiedlova of Slovakia for a quarter-finals spot.