Naomi Osaka has withdrawn from the WTA Finals in Shenzhen.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

Hazlewood takes six wickets as Australia win first Test
Bethell returns as England name squads for Australia white-ball tour
Rwanda to bring F1 back to Africa for first time since 1993
Ronaldo on target as Al-Nassr win after security delay
Coventry savour first home Premier League win in 25 years
