Kim Clijsters will be out of action for at least eight weeks after tearing the ligaments in her ankle during her Australian Open semi-final on Thursday.
"I have been to the hospital for a scan and it is bad news -- I will be out for at least eight weeks," the 22-year-old Belgian said on her website.
"All I can do with this injury is wait for it to heal and rest. It is very frustrating."
Second seed Clijsters was forced to retire from her match against France's Amelie Mauresmo in Melbourne after falling and hurting her right ankle during the third set.
Mauresmo led 5-7, 6-2, 3-2 and will meet Belgium's Justine Henin-Hardenne in Saturday's final.
Clijsters, who has been plagued by injury over the last two years, is still guaranteed to regain the world number one ranking from American Lindsay Davenport.
She was due to take part in the Antwerp Diamond Games on February 15 and organisers ordered more than 10,000 bottles of champagne as free gifts to mark Clijsters becoming number one.
Despite her injury, organisers said they expect her to attend as a spectator and would fulfil their promise to her fans.
