No.18 seed Ekaterina Alexandrova moved into the Miami Open quarterfinals after 2021 runner-up Bianca Andreescu retired from their match on Monday night due to a left ankle injury. Alexandrova advanced with the final score of 7-6(0), 0-2, ret.

Alexandrova won the streaky first set with a commanding 7-0 tiebreak, but Andreescu took an early 2-0 lead in the second set. However, Andreescu suffered her injury and sank to the ground during that game, and she was taken off court in a wheelchair. 

"I’m just really sorry that it happened to [Andreescu]," Alexandrova said afterwards. "Seeing her on the court in so much pain, it’s just painful to watch. You cannot help, you just can do nothing, which is terrible. And I think she’s going to be fine soon, and I’m wishing for her speedy recovery.

"The first set was super tough and great, and it probably could be a pretty good match for both of us, but unfortunately [Andreescu’s injury] happened."

Alexandrova will play No.15 seed Petra Kvitova in the quarterfinals on Wednesday. Kvitova booked her quarterfinal spot by grinding past surging qualifier Varvara Gracheva 7-5, 7-6(5) in just over two hours.

The first set of Alexandrova's match with Andreescu was interrupted by a two-hour rain delay at 3-2, but after play resumed, Alexandrova took control with powerful groundstrokes to lead 5-3. Andreescu broke back for 5-5, but Alexandrova regrouped, taking the tiebreak without the loss of a point.

"I’m really pleased with the fact that I was able to refocus [in the first set], because the start was really slow, I couldn’t find the rhythm," Alexandrova said. "After the rain, I just tried to do my best that I could, and just improve mistakes that I made in the start."

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Kvitova overcomes Gracheva

Earlier, two-time Wimbledon champion Kvitova booked a spot in her fourth career Miami Open quarterfinal with a close win over Gracheva, who is having a breakthrough season and is ranked at a career-high No.54.

Kvitova had to stare down five break points in the opening set, but the former World No.2 swatted all of them away while converting one of her two break points to steal the one-set lead.

Miami: Kvitova powers past Gracheva into quarterfinals

Gracheva, who reached her first WTA singles final a month ago in Austin, built a 5-2 advantage in the second set, but Kvitova pulled all the way back to line up a tiebreak.

Kvitova then saw a 5-1 lead in the breaker completely disappear, but from 5-5, she hit an ace and a forehand winner on the sideline on the last two points to close out the hard-fought win.

Kvitova is a win away from making the Miami Open semifinals for the first time in her 13 main-draw appearances at the event. She won her only prior contested match with Alexandrova in the third round of the 2020 Australian Open 6-1, 6-2.