World number one Aryna Sabalenka’s 20-match winning streak at the Wuhan Open came to an end as Jessica Pegula rallied from 5-2 down in the deciding set to win and set up a final against Coco Gauff.
Sabalenka had won in Wuhan in each of the past three tournaments and looked set to reach the final again when she broke twice to take command of the third set.
But 31-year-old Pegula dug deep to win four games in a row.
Sabalenka survived two match points to force a tie-break but had nothing left as American Pegula won 2-6 6-4 7-6 (7-2).
Earlier, French Open champion Gauff put in a stuttering performance but secured victory over Jasmine Paolini to reach the final.
The 21-year-old beat the Italian seventh seed 6-4 6-3 in a match featuring 11 breaks of serve in a row to reach her first final since her win at Roland Garros in June.
Gauff may have won in straight sets but struggled on serve, being broken five times and serving seven double faults.
“I’m really happy with how I played today. It was tough, especially playing on the serve, but I did what I needed to do to get through,” Gauff said.
“Sabalenka and Pegula are great players, and I’ve lost to them both before. But overall, I’m just going to focus on my side of the court and try to control the things I can control.”