Coco Gauff survived a scare to beat Ukrainian qualifier Yuliia Starodubtseva in three sets and reach the China Open semifinals on Thursday.
The 2023 US Open champion will face Paula Badosa after the Spaniard ended the fairytale run of China's 595th-ranked Zhang Shuai in straight sets.
Gauff, seeded four, fought back to defeat 115th-ranked Starodubtseva 2-6, 6-2, 6-2 in Beijing.
The 20-year-old American recently parted ways with coach Brad Gilbert as she attempts to regain the form that brought her a first Grand Slam crown last year.
Gauff's serve has become a particular problem and it was so again as she surrendered the first set.
But Gauff recovered her poise to battle back in the second – it was the first set Starodubtseva had dropped in her seventh match at the tournament.
Gauff, who is chasing an eighth singles title, surged into a 3-0 lead in the deciding set on the way to sealing her place in the semifinals.
ZHANG'S DREAM RUN ENDED
In the other quarterfinal on the day, former world No 2 Badosa disappointed the home fans with a 6-1, 7-6 (7/4) defeat of Zhang.
The 35-year-old Zhang, a two-time Grand Slam singles quarterfinalist who has been plagued by injury, arrived in Beijing on a run of 24 defeats in a row.
The painful losing run, stretching more than 600 days, was the second-longest on the WTA Tour in the Open Era, which began in 1968.
But the former top-25 player finally won a match to start her tournament and then rattled off three more victories to improbably reach the last eight.
In front of a near-capacity crowd at the 15 000-seater Diamond Court, Zhang went a double break down in a blur of unforced errors.
She finally held to get on the board for 4-1, but Badosa raced away with the first set in 23 minutes.
The second was closer and they went to a tiebreak.
Badosa, who is looking to win a fifth singles title, sealed the deal on her first match point when Zhang's forehand return drifted wide.
Zhang was the lowest-ranked player ever to reach this stage at the China Open.
Top seed Aryna Sabalenka plays Karolina Muchova on Friday for a place in the last four.
The winner will face Russian teenager Mirra Andreeva or China's Olympic champion Zheng Qinwen.