Mark Philippoussis is almost certain to miss this month's Australian Open after he was forced to pull out of the Hopman Cup because of a groin injury.

The Australian suffered two tears to his adductor muscle and though he said he was still hopeful of playing in Melbourne, doctors said he is unlikely to be fit in time for the year's first Grand Slam event, which starts on January 17.

"There are two tears of two centimetres diameter in his groin," said Hamish Osborne, the Hopman Cup tournament doctor. "It would be very unlikely in my opinion for him to do a five-setter once, let alone two days in a row, inside two weeks.

"The injury is more common in [Australian Rules] football, and a fit footballer would normally take three to four weeks to recover fully. Mark's injury is slightly different. It will always respond to treatment but he has to strengthen it enough to cope with repetitive days of tennis."

Philippoussis suffered the injury in the final set of his match against Dutchman Peter Wessels on Thursday, and though he completed the set, was unable to play the deciding mixed doubles.

Philippoussis, however, refused to give up hope of playing his home Grand Slam.

"It's tough to say [how long]," Philippoussis said. "It's something I'll have to go by feel. I'll start treatment as soon as possible and try to strengthen it without tearing it any more."

The Australian has been beset by injury throughout his career, requiring multiple surgeries on his left knee and suffering from back and hip problems, though he refused to be bothered by his latest injury.

"Like they say, what doesn't kill you makes you stronger. I know I can come back from this and that's all that matters.

"It's nothing major. The most important thing is that my knee has come out fine.

"I have to stay positive and keep my head up. No matter how long it takes I have to do the right thing. It's just the start of the year and there's a long way to go."

Philippoussis added he was confident his best tennis was still ahead of him.

"I wouldn't be here if I didn't love it. I still have goals I want to achieve and I still want to prove to myself how good I can be.

"I am 28, people say time is running out, but I don't think so. Look at Andre Agassi [Images] ...that's an inspiration to me."

Agassi has won five of his eight Grand Slam titles after turning 29.

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