Coco Gauff extended her winning run to a season-leading 15 matches with victory over Veronika Kudermetova at the China Open.
The US Open champion is bidding for a third successive title and saved four set points in the opener against last week’s Tokyo champion Kudermetova before clinching a 7-6 (5) 6-2 win in Beijing.
Gauff will next face sixth seed Maria Sakkari, who battled to a 6-4 2-6 6-3 victory over home hope Wang Xinyu.
World number one Aryna Sabalenka is also through to the quarter-finals after seeing off unseeded Italian Jasmine Paolini 6-4 7-6 (4).
That set up an Australian Open final rematch against fifth seed Elena Rybakina, who defeated 16-year-old Mirra Andreeva on Wednesday.
Sabalenka won one of the matches of the season in Melbourne but lost to her rival in the Indian Wells final.
“I know that I’ll have some chances to win this match,” said the top seed. “In the last match I lost, I got nervous a little bit and I rushed a little bit more. The key against Elena is just to stay calm, stay aggressive, and not over-rush things.”
Ninth seed Caroline Garcia is also through to the last eight after defeating Anna Kalinina 6-3 6-2.