Zheng Qinwen crushed Jasmine Paolini to secure a place in the WTA Finals last four on her tournament debut.
The 22-year-old, China's Olympic gold medallist in the summer, showcased her power in an easy 6-1 6-1 win that eliminated Italian Paolini.
It left Zheng with a 2-1 group-stage record, with her sole loss coming against Aryna Sabalenka on the first day of the tournament.
She is the first Chinese woman to reach the semi-finals of the tournament since the legendary Li Na in 2013.
"I didn't know what would happen when I came here," said Zheng.