'Everything came back': Petra Kvitova breaks down at French Open

The harrowing memories of a 2016 knife attack have come flooding back to Petra Kvitova at the French Open.

Kvitova was reduced to tears after a regulation straight sets win saw her cruise into the quarter-finals of the grand slam tournament.

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For a player who holds two Wimbledon titles, booking a place in her 13th grand slam quarter-final would not normally be that big a deal.

But this was different. Which is why the No.7 seed's emotions swelled and her eyes watered after she beat China's Zhang Shuai 6-2 6-4 at Roland Garros, where she hadn't reached the round of eight since 2012.

Poignantly, this was the tournament where Kvitova made her tennis comeback three years ago, following a harrowing home invasion in December, 2016.

The Czech star was badly shaken after the knife attack that left her with serious injuries to her racket-swinging left hand and with doubts about whether she'd ever play again.

After her victory on Court Philippe Chatrier, those memories came bubbling to the surface as a teary-eyed Kvitova was overcome with emotion.

The 30-year-old explained what was going through her head during a post-match press conference.

"My memories. Happy memories ... Everything just came back to me," said the No. 7 seed, who next faces Laura Siegemund, a first-time grand slam quarter-finalist.

"When I'm talking, I'm getting emotional again. It's been a long ride, definitely. Everything came to my mind - my whole family, people who I loved, (who helped) me through the tough, tough time," Kvitova said.

"I don't know, just everything came back."

Aus Open champ through to quarter-finals

Siegemund booked her place in the last eight with a 96-minute 7-5 6-2 win over Spain's Paula Badosa.

The 32-year-old German's best run at a slam continues, which was previously a third round appearance at both the Australian and US Opens in 2016.

American fourth seed Sofia Kenin appeared to be unnerved by the cheers of the sparse partisan crowd as she recovered from a wobbly start to reach the quarters with a 2-6 6-2 6-1 victory over France's Fiona Ferro.

The Australian Open champion, who next faces compatriot Danielle Collins or Tunisian Ons Jabeur, broke into tears after ending the contest.

"The crowd wasn't the best, which is understandable, but still I wish it would have been a little bit different," she told a news conference.

"I tried to use that as motivation. Obviously I was not really too happy with how it was going. I knew it's expected. I understand why. I'm playing a French player, and she's had a great run here."

A maximum of 1,000 spectators are allowed per day at Roland Garros amid COVID-19 restrictions, and around 500 attended the match on court Philippe Chatrier, voicing their support for Ferro.

with AAP

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