Naomi Osaka has withdrawn from the WTA Finals in Shenzhen.
The world number three from Japan picked up a shoulder injury after beating Petra Kvitova in three sets in her opening match on Sunday.
She'll now be replaced by alternate Kiki Bertens.
"I look forward to getting healthy and hope to be back here in Shenzhen next year," said Osaka.
"I'm disappointed to have to withdraw. This is not how I wanted to end this tournament or my season."

Police detain organiser of Messi visit after Indian fans rip up seats
Patel dominates as Mumbai take Game 1 of United Series
UAE though to Arab Cup semi-finals after beating Algeria on penalties
Dubai Basketball claim thrilling win over Bayern Munich in EuroLeague
