US Open: Swiatek stunned in fourth round as Djokovic cruises into quarter-finals

Iga Swiatek was stunned in the fourth round of the US Open on Sunday by Jelena Ostapenko and will lose her world No 1 ranking, while Novak Djokovic marked his imminent return to top spot by easing into the quarter-finals.

Siwatek, the top seed and defending champion, looked on course for victory when she took the opening set against Ostapenko, but the Latvian stormed back to win 3-6, 6-3, 6-1 and secure her fourth victory in as many meetings with the Polish star.

The mercurial Ostapenko, who had never made it to the last 16 in New York before this week, goes on to face title contender and home favourite Coco Gauff in the last eight.

"She plays well against me, she's always done that," said Swiatek. "I'm just surprised that my level changed so drastically. I don't really know what happened with my game, I felt no control suddenly."

Undeterred by falling behind, Ostapenko's typically fearless and aggressive approach rendered Swiatek helpless and ensures there will be a new world No 1 after the US Open. Swiatek's 75-week reign will come to an end, with rival Aryna Sabalenka set to take over top spot.

"I always expect a tough battle against Iga, she's such a great player and won many Slams and is so consistent," said Ostapenko, the 20th seed and 2017 French Open champion.

"I knew I had to be aggressive and play my game because that's what she doesn't like. I was just thinking that I have to play until the very last point, until we shake hands. I felt like I was playing better and didn't give her many chances."

Gauff ended Caroline Wozniacki's fairytale Grand Slam comeback earlier on Sunday as the sixth seed saw off the former world No 1 6-3, 3-6, 6-1.

Coco Gauff celebrates her win over Caroline Wozniacki. AFP

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