MELBOURNE, Jan 14, 2008 - Roger Federer believes his old coach Tony Roche could revive the fortunes of former world number one Lleyton Hewitt.

　　The 12-time Grand Slam champion spilt with the veteran Australian mentor before last year's French Open after two-and-a-half years working together.

　　The Swiss champion, who gets his Australian Open campaign underway here on Tuesday against Argentine Diego Hartfield, said Hewitt could only benefit from having Roche working with him.

　　"Lleyton's a pretty good player already. He's been number one in the world, he's won his fair share of Grand Slams, the most important ones," Federer said Monday.

　　"He obviously hopes to win this one. It's the big goal for him every year. There's big talk around Lleyton every time.

　　"I'm sure Tony can teach him some stuff. I think you never know enough, so it's good to have a guy like Tony on his side, for sure."

　　While it was the now-coachless Federer's call to end their partnership which yielded six Grand Slam titles, he said it was no easy decision.

　　"Of course, it's a pity that we're not together anymore," Federer said.

　　"It was a tough blow in some ways, the way it didn't work out. But sometimes that's the way it goes.

　　"It's been a bit of a change obviously. It was hard - just before the French Open - and I've had to definitely adjust my practice sessions accordingly, getting really well organised with practice partners, sparring partners."

　　Hewitt and Federer are in the same half of the draw here but although he expects Roche to have some inside knowledge on the Swiss star, Australia's great hope said it was too early to start thinking about a semi-final showdown.

　　Hewitt, a former US Open and Wimbledon champion who has struggled to revisit that sort of form, insisted he was only focusing on getting past rising Belgian Steve Darcis in his opening match on Tuesday.

　　"You need a little bit of luck in any Grand Slam to win it and for me right at the moment, it's just a matter of trying to survive the first week," said the Australian.

　　Hewitt is currently ranked 22 in the world.