Imperious Jessica Pegula defeats Maria Sakkari to continue unbeaten run at WTA Finals

The World number five had already secured her spot in Saturday's semi-finals by beating both Sabalenka and Rybakina in her earlier matches in Cancun.

But the American is yet to drop a set so far this tournament and it took her just under 80 minutes to beat Sakkari 6-3 6-2, who failed to qualify for the semi-finals after losing all of her games.

"I think last year when I became Top 5, I felt maybe I psyched myself out a little bit - not a lot - but just a little bit," Pegula reflected. 

"You have a couple of thoughts in your head if you really belong at that level. I was always good at beating everyone below me. But it's like now you have to beat the one or two before you, and I think you put a bigger emphasis on that. 

"This year, I've just not really cared and I've just had, I think, more confidence in those matches. And that's why I think I've had some maybe better top wins this year as far as beating No.1 players in the world in big moments, like here and in Montreal."

Meanwhile, fighting for a spot in the semi-finals, world number one Aryna Sabalenka and world number four Elena Rybakina had their match suspended due to wet weather.

Sabalenka won the first set 6-2 in the Australian Open final rematch on a rain-interrupted evening and had Rybakina on the ropes early in the second set.

But Rybakina fought back to take the lead 5-3 before the match was called off for the night, with play to resume on Friday.

Also on Friday, Iga Swiatek will take on Ons Jabeur while Coco Gauff plays Wimbledon champion Marketa Vondrousova to decide who makes the semi-finals.

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