Simona Halep saved a match point before defeating Canadian teen Bianca Andreescu 3-6, 7-6, 6-3 at the WTA Finals in Shenzhen.
Both players sought medical treatment during the match, with Halep getting her foot treated while Andreescu had a lower back problem.
Elsewhere, defending champion Elina Svitolina stretched her unbeaten run at the season-ending tournament with a 7-6, 6-4 win over Karolina Pliskova.
Halep and Svitolina are now 1-0 in the Purple Group, while Andreescu and Pliskova are 0-1.
UAE, Saudi Arabia set for Gulf Cup final showdown
The UAE face hosts Saudi Arabia in the final of the 27th Arabian Gulf Cup on Tuesday in Jeddah, with both sides aiming to end long waits for regional football's most prestigious title.
Djokovic wins China Open as de Minaur retires injured
Novak Djokovic won his seventh China Open title after Australia's Alex de Minaur retired with a groin injury during the final on Tuesday.
Alcaraz sinks Lehecka to retain Japan Open crown
Defending champion Carlos Alcaraz defeated unseeded Czech Jiri Lehecka 7-6(4) 6-4 in the Japan Open final on Tuesday to retain his title and continue his resurgence after a wrist injury.
McIlroy set for Dubai return at DP World Tour Championship in November
Seven-time Race to Dubai champion Rory McIlroy will tee it up at the DP World Tour Championship from November 12-15 at Jumeirah Golf Estates in Dubai, as he bids to draw level with Colin Montgomerie's record haul of eight Harry Vardon Trophies.
Kaur steps down as India women's team captain
World Cup-winning skipper Harmanpreet Kaur announced on Tuesday her decision to step down from her role as captain of the Indian women's team in all formats.
