NEW YORK, NY, USA - American qualifier Jessica Pegula is into the biggest quarterfinal of her career after fighting past No.5 seed Aryna Sabalenka in three sets at the Western & Southern Open. 

With four tough matches already under her belt in New York - including an upset over Amanda Anisimova in the second round - Pegula was dialed in from the start against the Doha champion. She weathered a mid-match dip as Sabalanka fought her way back, but Pegula stayed solid to claim her career-best win-by-ranking over the World No.11, 6-2, 2-6, 6-2 to move into her first Premier 5 quarterfinal. 

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“I think it’s really great, I’ve beat three really top players right now, Top 50 players, and that gives me a lot of confidence going into the quarters,” Pegula told after the match.

“I’m definitely happy, but it doesn’t really feel like the quarters because I played qualifying - it kind of feels like it should be a final!” Pegula added with a laugh. “But I definitely want to take this and use it as momentum going into the US Open.”

2020 Cincinnati highlights: Pegula sinks Sabalenka to seal quarterfinals

Pegula fired 10 winners and didn’t commit any unforced errors in a rollercoaster opening set that opened with five consecutive breaks of serve. It was the American qualifier who kept her nose in front, getting out to a 2-0 lead and taking advantage of Sabalenka’s double faults to break again, 3-1. 

Pegula recorded the decisive service hold to make it 5-2, and was firmly in control of proceedings as she broke Sabalenka once more in a lengthy final game to claim the set, 6-2.

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But Sabalenka showed why she’s become one of the tour’s top contenders as she raised her level in the second set. Sabalenka pressured Pegula and was rewarded with a run of five games in a row, securing a double break to create a 5-1 lead. Sabalenka leveled the match after closing out the set, 6-2. 

Pegula and Sabalenka were locked in battle throughout the tight final set, but it was Pegula who broke away with a break at 3-1. It proved to be decisive, as she fought off two more break-back opportunities to seal the match with an ace after two hours and eight minutes. 

“I knew there were going to be streaks where she was going to play really well,” Pegula said. “I thought maybe my pace could hurt her a little bit, if I could get her moving to her backhand and not let her set up too much on her forehand. I thought I did that pretty well, and I thought I returned really well."

It’s already the fourth quarterfinal of the year for the on-the-rise Pegula, who opened the season with a run to the final at the ASB Classic in Auckland, falling to Serena Williams in the title match. She backed it up with quarterfinals at the WTA 125K level in Newport Beach and Indian Wells before the tour’s five-month lockdown.

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Up next for Pegula will be No.15 seed Elise Mertens, Sabalenka’s doubles partner. The Belgian defeated Veronika Kudermetova in a straightforward 6-2, 6-3 victory earlier in the day to advance.