China's Zheng Qinwen beat a struggling Elena Rybakina 7-6(4) 3-6 6-1 in a grueling WTA Finals group stage match on Monday, notching her first career win over the Kazakh in their third meeting.
Seventh seed Zheng bounced back from her initial round-robin loss to Aryna Sabalenka to become the second Chinese player, after Li Na, to claim a victory at the Finals, since the tournament's inception in 1972.
The win puts seventh seed Zheng (1-1) in contention for a semi-final spot when she plays Jasmine Paolini on Wednesday, while the 25-year-old Kazakh is now 0-2 with one round-robin match remaining against Sabalenka.
Zheng started strong, taking an early edge in the tiebreak. Rybakina rallied in the second set, using her serve to fend off break points and later securing a break of her own to level the match.
In the decisive set, Zheng punished a string of fatigued forehands from the Kazakh, sealing her victory after a break in the sixth game.
Rybakina suffered her second loss in Riyadh after entering the tournament on the back of fitness issues. Zheng, by contrast, entered it after winning titles in Palermo and Tokyo, and an Olympic gold in Paris.
"I'm really happy to win this match because I'd never beat her before and she's one of the greatest players right now on tour," Zheng said.
"Even though I had a chance in the second set and didn't take it, I'm happy I came back in the third set and stayed focused."
World number one Sabalenka is playing fourth ranked Italian Paolini in the evening match
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