Olympic champion Zheng Qinwen of China claimed a 5-7, 6-0, 6-4 victory over Mirra Andreeva, advancing to her first WTA 1000 semifinal on Friday.
The 17-year-old Andreeva started strong for a 4-0 lead. Zheng fought back with better serves, earning a chance to serve out the set at 5-4, only to see Andreeva answered by breaking her twice to claim the first set.
Zheng swept up the second set by racing through six consecutive games, bringing the match to a deciding set, where she took four games in a row when trailing by 2-4 for the eventual victory.
"At the beginning of the match I was trying to be calmer, trying to be more gentle with the opponent because I know she's much younger," said Zheng, who is about to turn 22 next week. "But after what I see with my tennis today, I say, 'I'm not going to win today by my tennis, I'm going to win today by my mentality.'"
Zheng is the first Chinese semifinalist in China Open since Wang Qiang in 2018.
"There is always extra motivation to play on home court, because I know all the crowd are coming to support me," she said.
Zheng will face US Open semifinalist Karolina Muchova in the semifinals on Saturday.