Czech seventh seed Petra Kvitova overcame a slow start to beat Canadian teenager Leylah Fernandez and reach the French Open fourth round.

She will face China’s Zhang Shuai for a place in the quarter-finals.

Earlier, Australian Open champion Sofia Kenin advanced with a 6-2 6-0 win over Romanian qualifier Irina Bara.

But eighth seed Aryna Sabalenka was beaten by Tunisia’s Ons Jabeur 7-6 (9-7) 2-6 6-3.

The 26-year-old will next play American Danielle Collins, who knocked out Spanish 2016 champion Garbine Muguruza 7-5 2-6 6-4 in a match that began on Court Simonne Mathieu but was moved under the roof on Philippe Chatrier after rain halted play in the second game.

Muguruza, seeded 11th, looked to be heading for victory when she led by a double break at 3-0 in the final set but fell away badly as 2019 Australian Open semi-finalist Collins rediscovered the intensity that won her the first set.

For Kvitova, 30, this is the first time she has reached the fourth round at Roland Garros since 2015.

The opening few games were error-strewn from the Czech, who struggled against a fellow big-hitting left-hander.

Fernandez won the girls’ singles title at Roland Garros last year and looked assured as she won five games in a row in the first set.

However, Fernandez could not find a first serve and Kvitova pounced, winning six games in a row to close out the opener.

Kvitova still had to fight in the second set, saving four break points before a forehand winner secured victory.

“She pushed me a lot. I really had to fight until the end. I managed to win it somehow,” Kvitova said.

Jelena Ostapenko, the Latvian 2017 Roland Garros champion who knocked out second seed Karolina Pliskova in the previous round, lost 6-4 6-3 to Paula Badosa.

The unseeded Spaniard will face German Laura Siegemund next after the 32-year-old beat Croat 13th seed Petra Martic 6-7 (5-7) 6-3 6-0.

Sabalenka out but Kenin breezes through

Kenin earlier won 12 games in a row to beat Bara, hitting 32 winners and saving 10 break points.

She will face Fiona Ferro next after the Frenchwoman’s 7-6 (9-7) 4-6 6-0 win over Patricia Maria Tig of Romania.

Belarusian Sabalenka has been a top-16 seed at the past seven Slams but has failed to make it to the second week at each tournament.

She lost a fluctuating match against Jabeur, who has reached the fourth round in Paris for the first time.

Jabeur had triple set point at 6-5 in a scrappy first set but was broken, before storming back from a 5-1 deficit in the tie-break to take the opener in 57 minutes.

However, a refocused Sabalenka took the second in just 19 minutes to force a decider.

Sabalenka saved three match points but sent a forehand long to hand Jabeur victory.

Jabeur arrived for her post-match news conference with a face mask that had a cartoon of men’s fifth seed Stefanos Tsitsipas on, with Jabeur joking she was “Team Tsitispas”.

Kvitova’s fourth-round opponent Zhang earlier reached the fourth round with a 7-6 (7-2) 7-5 win over French wildcard Clara Burel.