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 second Chinese woman to reach the semi-finals of the tournament following the legendary Li Na in 2013.
“I didn’t know what would happen when I came here,” said Zheng. “I just told myself to enjoy it, especially because I am in a really difficult group.”
Having already clinched the year-end world number one ranking, Sabalenka will top the group if she beats Elena Rybakina later on Wednesday.
The tournament, contested between the top eight singles and doubles players, offers record prize money, with an unbeaten singles champion set to collect just under £4m.
The WTA Finals are being held in Saudi Arabia for the first time – a move which has been criticised by some because of the country’s human rights record.
Crowds at the season-ending contest have appeared disappointing – Tim Henman was among those who criticised the low turnout for Iga Swiatek’s opening match on Sunday – but Zheng has been a consistent draw.
The world number seven, runner-up to Sabalenka at this year’s Australian Open, overwhelmed Wimbledon and French Open runner-up Paolini with her huge forehand and solid serve.
Zheng hit 24 winners and 12 aces during the 67-minute win, with the 28-year-old Paolini unable to match the powerful hitting.
It is the first time Zheng has beaten two top-10 players at the same tournament, having overcome world number five Rybakina in three sets earlier in the week.
Since her Olympics success in Paris, Zheng has won titles in Palermo and Tokyo, as well as reaching the quarter-finals of the US Open and the Wuhan Open final.
