Former world number one Lleyton Hewitt may be forced to withdraw from this year's French Open and Wimbledon championships due to a hip injury.
The former Wimbledon and U.S. Open champion has been undergoing treatment and tests at a Sydney hospital and is waiting on the results to determine when he can resume playing.
After a month on the sidelines, Hewitt admits he is unsure how his body will hold up when he returns to the court.
"The hip is starting to feel a little better but I'm yet to fully test it out on court," Hewitt said.
"The specialist did a couple more tests today but the results won't be back for a few days. Once I get those I can make a decision on the French Open and the grass court season."
The hip injury is the latest in a series of setbacks that have plagued the 27-year-old since he lost the world number one ranking in 2003.
Hewitt won the U.S. Open in 2001 and Wimbledon the following season but has not won a grand slam title since and has steadily slipped down the rankings to 19th.

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