Sara Bejlek stuns world number one Aryna Sabalenka in Cincinnati

Beljek reached herfirst-ever WTA 1000 quarterfinal when she toppled the world number one 7-6(7), 6-4 on the hard courts of Cincinnati. But the 20-year-old Czech had to graph.

Beljek battled back from 2-0 down in the opening set to force a tiebreaker, where she found herself 5-1 up. Then Sabalenka rallied to make it 5-5. Bejlek was able to close out the first set 7-6 (9-7) on her third set point in the tiebreak.

In the second, Sabalenka had things under control, 4-1 up. But again Bejlek fought back, taking advantage of a weak Sabalenka serve which produced zero aces and four double faults. She sealed the win in just under two hours.

"I feel incredible," a shocked Bejlek said on court.

"I lost totally my words. I just keep believing and that was the key today. She played amazing tennis and I was just believing, keep fighting and I was just trying my best and that's it."

"In this moment, I don't really know. I will talk to my team and let's see what they will tell me what to do and I will try my best and do the rest of it."

She will next face American and 2019 champion Madison Keys. The American advanced to her first WTA 1000 quarterfinal of the season after a close 7-6, 6-4 win over Xiyu Wang.

Elsewhere, fourth seed Coco Gauff defeated Marie Bouzkova 6-3, 6-2 to book her place in the last eight.

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