Naomi Osaka, 24, has been away from tennis since the US Open in September.
She has openly told about anxiety and depression, but in Melbourne she was back.
There she made it to the semifinals and was to face the Russian Veronika Kudermetova, but now she is forced to withdraw due to an abdominal muscle injury.
"Sorry to withdraw from my match due to injury.
My body got a shock from playing match two intense matches two days in a row.
Thank you for all the love this past week ", she writes on Twitter.
Osaka's plan is to play the Australian Open soon.
In Melbourne, Kudermetova and Simona Halep meet in the final.
60 seconds: Naomi Osaka fight in the spotlight
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60 seconds: Naomi Osaka's fight in the spotlight Photo: TT News Agency / Screenshot