Jule Niemeier saved two set points in the first set en route to scoring a 7-6(9), 6-1 upset of No.10 seed Petra Kvitova in the second round of the Mutua Madrid Open.

The result was the 23-year-old's second career Top 10 win following her defeat of Anett Kontaveit in the second round of Wimbledon last year, which she rode all the way to her maiden Grand Slam quarterfinal.

Niemeier has struggled to reach a similar level so far in 2023. Her win over Kvitova was just her fifth in 17 matches this year, and Madrid marks the first time she has won back-to-back matches since October 2022. But a three-set defeat of Beatriz Haddad Maia in Billie Jean King Cup action two weeks ago was a promising sign that the German was beginning to turn her season around, and her power game was on song against Kvitova.

Three-time Madrid champion Kvitova was in action for the first time since capturing her 30th Hologic WTA Tour title in Miami, and competing in the 100th WTA 1000 tournament of her career. But the Czech had been forced to withdraw from Stuttgart last week due to a right foot injury, and fell to her fourth straight loss in Madrid.

Niemeier comes up clutch: Kvitova won the longest tiebreak of 2023 so far to win the Miami final 7-6(14), 6-2 over Elena Rybakina, and she found herself embroiled in another overtime decider in a tightly-contested first set. Both players had missed opportunities to close it out earlier: Niemeier had held two set points on Kvitova's serve at 5-4, and Kvitova had served for the set at 6-5.

Niemeier sprang out to an early lead again in the tiebreak, only for Kvitova to come up with her biggest shots to save a further four set points. But Niemeier responded well, fending off two against her before taking advantage of a stroke of luck -- a dead net cord at 9-9 -- and converting her seventh opportunity.

With the first set under her belt, the World No.67 raced through the second as Kvitova continued to rack up a total of 53 unforced errors to only 24 winners. Niemeier, who displayed fine touch as well as power with several successful drop shots, will go on to face either No.24 seed Elise Mertens or Rebecca Marino.