(CNN) -- Roger Federer and Serena Williams go into next week's Australian Open as top seeds but tennis legend Boris Becker says they will have their work cut out to claim the opening grand slam of the season.
Becker told CNN both singles titles would be hotly-contested with a clutch of contenders laying claim to eventual glory in just over two weeks time at Melbourne Park.
The six-time grand slam champion said Federer's recent record could count against him after the Swiss star came unstuck at the ATP Tour finals in London and in Doha, where he was beaten by eventual champion Nikolay Davydenko.
"On paper you should usually go with the number one player in Roger Federer, but he has not won a tournament lately and I have a good feeling about Rafael Nadal, who is the defending champion," said the German.
"He has something to prove and he is injury free," added Becker, who believes that Nadal was disadvantaged in returning to action late last summer after an injury layoff, on his least favorite hard court surface.
But given the unpredictability at the top of the men's game at the moment, Becker says that it would be dangerous to underestimate Federer, beaten by Nadal in a five-set final classic last year.
"He's at the stage of his career when he only gets up for the grand slams and Melbourne starts we are going to see the very best of Roger Federer."
Becker's other tips to make an impression are U.S. Open champion Juan Martin Del Potro and fifth seed Andy Murray of Britain, who has yet to win a grand slam.
"He needs to get that monkey of his back," Becker said of Murray.
"The courts in Melbourne suit his game, he's got the tools and has got to prove it."
Add in the likes of Davydenko and 2008 champion Novak Djokovic and the men's title race looks too close to call, while Becker believes the return of Belgian pair Kim Clijsters and Justine Henin has give the women's draw a real shot in the arm.
Becker bemoaned the fact that Dinara Safina was installed as world number one for much of last year, despite never winning a grand slam, and said Clijsters remarkable return to claim the U.S. Open came not a minute too late.
"That incredible comeback win encouraged Justine to come back and that's going to be the story for the Australian Open," he said.
"It will be the Belgian 'sisters' versus the Williams sisters for the title," joked Becker, while adding that he expected Serena to successfully retain her title.
Add in consistent Russians Safina and Elena Dementieva, not to mention the return to near her best of their compatriot and 2008 champion Maria Sharapova and the depth of competition in the women's singles almost stands comparison with the men's draw.
The first strokes in anger will be played next Monday with first round action in both the men's and women's singles.
Australia has been gripped by a summer heat wave with near-record temperatures and the action of court is promising to be just as hot.