Naomi Osaka pulled out of next week's Berlin WTA 5000 grasscourt tournament on Monday, raising doubts about the four-time Grand Slam champion's participation at Wimbledon later this month.
The decision comes after Japanese world number two Osaka pulled out of the French Open last week on mental health grounds.
"We have received notification Naomi Osaka cannot start in Berlin. After consulting her management, she will take a break," Berlin event organisers said in a statement ahead of the tournament which begins on June 14.
Osaka has not revealed when she plans to play next, casting doubt on her participation at Wimbledon, which starts on June 28, and the Tokyo Olympics next month.
The 23-year-old released a short social media statement on Saturday to thank her fans for their support over her decision to withdraw from the French Open following a dispute over her refusal to attend press conferences.
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