Australia's Lleyton Hewitt [Images] remains a doubt for next week's French Open despite being cleared of serious injury.

Hewitt twisted his right ankle playing a warm-up tournament in Austria on Monday but scans showed there was no ligament damage.

However, Hewitt's manager Rob Aivatoglou told Australian media on Thursday the former world number one was still not certain of playing in Paris.

"The MRI didn't show any structural damage," Aivatoglou told the Daily Telegraph. "But we've still got to wait to see how the injury responds to treatment over the next couple of days."

Hewitt's unsure status will come as bad news for organisers with Andy Roddick's [Images] participation also in doubt.

The American landed heavily on his left foot during a match in Germany [Images] on Wednesday and needed lengthy treatment.

"I just hope I wake up tomorrow and it resembles an ankle and not a balloon," the world number five said.

"It's just annoying. It's disappointing. I feel like every time there's progress being made something happens and there's a little bit of a setback," Roddick added.

Hewitt missed last year's French Open when he cracked a rib at his Sydney home and has been plagued by more health problems in the build-up this year, pulling out of last week's Hamburg Masters because of a leg problem.

Hewitt had been planning to use the French Open as part of his preparations for Wimbledon. Hewitt won the Wimbledon singles crown in 2002 and the US Open the previous year but has not won a Grand Slam title since.

He reached the US Open final in 2004 and the Australian Open final in 2005 but has never made it past the quarter-finals at Roland Garros.

The French Open runs from May 29 to June 11.

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