Naomi Osaka has withdrawn from the WTA Finals in Shenzhen.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."

Dave Rennie becomes first Pacific Islander to lead All Blacks
FIFA offering $12 tickets to World Cup Play-Off Tournament
Resurgent Wolves stun Liverpool, Everton enjoy home comfort
Real Madrid's Rodrygo to miss World Cup for Brazil
Getafe stuns Real Madrid to shake up LaLiga title race
