Petra Kvitova saved four match points and survived a marathon third-set tiebreaker to emerge with a 6-2, 3-6, 7-6 (11) win over Jessica Pegula in the fourth round of the BNP Paribas Open on Tuesday in Indian Wells, Calif.
Kvitova, a Czech player who is seeded 15th, fell behind by a service break three times in the final set but rallied each time. Pegula, a U.S. player who was seeded third, had her first match point while serving at 5-4, and she again had an opportunity to serve out the match after going up 6-5.
In the tiebreaker, Pegula failed on three match points and Kvitova failed on three match points before taking advantage of her fourth.
Kvitova said postmatch, "I just tried to still be aggressive, but it (was) not always was there for me. The emotions were of course very happy. And a little bit exhausted now."
Kvitova prevailed despite saving just one of five break points on her serve and putting only 57 percent of her first serves in play.
Next up for Kvitova, the Wimbledon champion in 2011 and 2014, will be a quarterfinal matchup with Maria Sakkari. The seventh-seeded Greek player defeated 17th-seeded Karolina Pliskova of the Czech Republic 6-4, 5-7, 6-3.
Sakkari beat Kvitova in the third round at Indian Wells last year en route to the final.
"I expect a big fight, for sure," Kvitova said. "That's normally (what) our matches look like. And I know that she's playing all three-setters here, as well as me, probably, so it will be a really close one, for sure."
Elsewhere on Tuesday, second-seeded Aryna Sabalenka of Belarus edged 16th-seeded Barbora Krejcikova of the Czech Republic 6-3, 2-6, 6-4, and sixth-seeded Coco Gauff of the United States topped Sweden's Rebecca Peterson 6-3, 1-6, 6-4. Tenth-seeded Elena Rybakina of Kazakhstan routed Russia's Varvara Gracheva 6-3, 6-0.
Romania's Sorana Cirstea upset fifth-seeded Caroline Garcia of France 6-4, 4-6, 7-5, and Karolina Muchova won an all-Czech showdown with Marketa Vondrousova, 6-4, 6-7 (2), 6-4.
In the final match of the night, top-seeded Iga Swiatek of Poland opposed Emma Raducanu of Great Britain in a matchup of former U.S. Open winners.
--Field Level Media