Bookies, experts, Federer is everyone's favourite for Aus Open

Roger Federer is the "clear favourite" to retain his Australian Open title over an injury-riddled field when the first grand slam of the season starts next week in Melbourne, tennis analysts said on Wednesday.

Federer's bid for a 20th grand slam title will be aided by the absences of Andy Murray and Kei Nishikori, as well as lingering injuries to top players who are still expected to play like Rafael Nadal and Stan Wawrinka.

But more so than the competition, it is the 36-year-old Federer's dominant play at this month's Hopman Cup, where he won all four of his singles matches and led Switzerland to a third title, that gives him the edge.

"He looks younger than ever," ESPN tennis analyst and former professional Patrick McEnroe told reporters on a call on Wednesday.

"He's moving as beautifully as ever. He's hitting the ball brilliantly. Wins four or five matches at the Hopman Cup against high-level competition. To me, he's the clear favourite."

Bookmakers are also expecting the world number two to successfully defend his title.

Federer ($2.75 AUD) is the favourite to win the tournament, according to Australian Gambling, with world number one and last year's Australian Open runner-up Nadal ($5.50) trailing him.

"He could always get picked off early," McEnroe said.

"But based on what I've seen so far... I don't think there's anybody else that you could say is a favourite other than Roger at the moment."

ESPN analyst and former world number one Chris Evert said his experience and smooth style of play, which has left him relatively injury-free, set him apart from the field.

"This is a guy who is so relaxed... I think that affects him mentally as well as physically," she said.

"Mentally and emotionally, having kids, having a family, he gets away from the game. He knows how to compartmentalise really well."

"He lets the losses roll off his back, there's no tension there. I think he has a real joy for the game," she said.

"That's what makes Federer, Federer."

The Australian Open runs from January 15-28.