CINCINNATI, OH, USA - No.13 seed Madison Keys survived a big test against Angelique Kerber to make her way into the quarterfinals at the Western & Southern Open.

Keys came into the match against No.4 seed Kerber trailing 1-7 in the pair’s head to head record - she hadn’t won a set against her in four straight matches and had never recorded a hardcourt win.

She snapped the streak in emphatic style, bouncing back from a sluggish start, firing 55 winners and nine aces to score a 2-6, 7-6(3), 6-4 victory after just under two hours on court.

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“Considering the last - what was it, six times? - it didn't go so hot, this victory feels good,” Keys said in press. “More than anything, it was just how I handled being down and not letting the previous results kind of spiral in my head for me. I think that's what I'm happiest with.

“I think that today specifically I was just really good at staying focused on a couple of things and not letting my mind wander or get ahead of myself or anything like that.”

The pair were all set to take the court at 1 p.m., but before they could play a point, the weather that had been wreaking havoc on the Cincinnati schedule delayed play once again.

Three and a half hours later, it was Kerber who started out on the front foot with an early break for a 2-1 lead. The unforced errors were leaking off of Keys’ racquet, and Kerber was rock solid and stayed aggressive to extend her lead to 5-1, comfortably closing out the set two games later.

Kerber faced more challenge in the second set as Keys found her rhythm and rallied the Cincinnati crowd behind her. The American earned her first break points at 2-2, but wasn’t able to convert. Kerber punished her for it in the next game, needing four break points to escape with the edge and the first break of the set.

But the American dug her heels in to break straight back in the next game at 3-3 and get them back on serve, her big groundstrokes firing off both wings. There wasn’t much to separate them in the five games that followed, each game going decisively to the server.

Keys found some big serves - including a big kick serve on her second delivery - to trouble Kerber, and fought off two set points to take them into a tiebreaker. After going down an early minibreak, Keys found another level to reel off six points in a row and send the match into a deciding set.

The American’s game only improved as the match went on, pouncing on every short ball and punishing Kerber’s second serves. After a tense eight games, it was Keys who earned the decisive break, serving out the match confidently to dispatch the Wimbledon champion in two hours.

Up next, Keys will face Aryna Sabalenka in the quarterfinals - the Belarusian stunned No.6 seed Caroline Garcia 6-4, 3-6, 7-5 later in the day.

“I know that she's a hard hitter and that she goes for her shots - honestly, that's really all I know,” Keys admitted. “I have seen bits and pieces here and there, but I haven't been able to sit down and focus on her strengths and weaknesses.

“I do know that [hard-hitting] game well. So I think it's just going to be a carryover from similar matches like that and focus on that, but obviously gonna have to study her a little bit more.”