Aryna Sabalenka reached the US Open quarter-finals for the fourth year in a row with an assured victory over Elise Mertens.
Second seed Sabalenka, beaten by Coco Gauff in the New York final last year, saw off her former doubles partner Mertens 6-2 6-4.
The Belarusian hit 41 winners and saved all eight of the break points that Belgium’s Mertens created.
Sabalenka is the first woman to reach four consecutive women’s singles quarter-finals at Flushing Meadows since Serena Williams in 2016.
She has now made the quarter-finals or better in her past eight Grand Slam appearances.
Her last defeat before that stage came at the 2022 Australian Open, where she was beaten by Kaia Kanepi in the fourth round. She has not lost a match in Melbourne since, winning the title in 2023 and defending it in January this year.
Sabalenka will face China’s Olympic champion Zheng Qinwen, who beat silver medallist Donna Vekic 7-6 (7-2) 4-6 6-2, in the last eight.
A match which lasted two hours 50 minutes ended at 2.15am local time on Monday, the latest finish to a women’s US Open match.
Sabalenka beat Zheng in the Australian Open final this year.
Paula Badosa earlier breezed past Wang Yafan 6-1 6-2 to set up a quarter-final against Emma Navarro, who ended Gauff’s title defence in a three-set win.
