World number two Kim Clijsters is to have an operation to remove a cyst from her wrist which is likely to put her out of action for three months.
Clijsters watched the French Open from the stands because of injury
In a statement on her website the world number two added that she would probably miss the US Open, a day after revealing she would sit out Wimbledon.
The 21-year-old has suffered problems with her left wrist since March and not played on the WTA circuit since May.
Prior to her injury, Clijsters had won tournaments in Paris and Antwerp.
"This is not really a great birthday... I have to be operated on on that cyst, that is a fact now," said Clijsters, who turned 21 on Tuesday.
"We could drain it with a needle but the chances are it could come back.
"It's better to remove it for that reason and also to prevent the tissue in my wrist from suffering any further damage.
"I want to have the operation as quickly as possible but there are some tests that still have to be carried out."