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.

'Big Show' Maxwell announces international retirement
Al Wasl edge Iraq's Al Quwa Al Jawiya in AFC Champions League Elite
Antonelli makes history as youngest F1 champion at 20 years old
Lionel Messi lifts Inter Miami past Revolution to move into second place in East
Dubai Ride 2026 sees over 40,000 cyclists on Sheikh Zayed Road