5:29 PM ET
Muguruza won 6-2, 6-7 (5), 6-3 after she served for the match at 6-5 in the second set before Sabalenka broke her serve and won the following tiebreaker.
“I just fight and stay there and keep thinking that I’m going to win,” Muguruza said. “If I have an opponent that is playing great, I have to play better.”
The 16th-ranked Spanish player will face Maria Sakkari of Greece in the quarterfinals. Sakkari won 6-2, 6-2 against Madison Keys in what was the American’s second match since returning to the tour after missing the Australian Open with the coronavirus.
Svitolina cruised through her match against Misaki Doi 6-1, 6-2. Svitolina was playing for the first time since a fourth-round loss at the Australian Open on Feb. 15, while Doi was on her fifth match in as many days after coming through qualifying. Svitolina’s quarterfinal opponent is Victoria Azarenka, who beat Laura Siegemund 6-4, 6-2.
Karolina Pliskova, seeded second, won 6-4, 4-6, 7-5 against Ons Jabeur to move to a 5-3 record in 2021 after a subdued start to the year including a third-round defeat to fellow Czech Karolina Muchova at the Australian Open.
Fourth-seeded Petra Kvitova prevailed 6-1, 6-3 in her second-round match with Anastasia Pavlyuchenkova after coming back from 3-1 down in the second set. Kvitova next plays Estonia’s Anett Kontaveit and will aim to win back-to-back matches for the first time in 2021.