Federer says Kyrgios could be a future Hall of Famer

Roger Federer has urged critics to lay off Nick Kyrgios, saying the Australian has the talent to be a Hall of Famer.

Kyrgios defeated Rafael Nadal at an Australia v World Fast4 showdown in Sydney last night before pulling out of the World Tennis Challenge event in Adelaide.

The Australian youngster is dealing with a knee injury that will require cortisone injections throughout his home grand slam.

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Kyrgios also dipped his toes into politics when he wore an anti-Donald Trump t-shirt at the Fast4 event.

"I won't give him that much advice just because I think he needs to do it all by himself," Federer told Seven News.

Roger Federer says Nick Kyrgios could be a future Hall of Famer. Pic: Getty

"It's the unknown with Nick. I think that's always going to be intriguing for people to follow.

"I think he's one of the biggest talents we have in the game right now and I just hope he can make the most of it with what he has and become a future Hall of Famer."

Federer enters the Australian Open ranked 17th in the world after a six-month break due to post-Wimbledon knee surgery.

The low ranking - by his standards - means the Swiss could face his rivals much earlier in the grand slam than usual but the 35-year-old isn't keen on making up the numbers.

"I do believe it's absolutely still possible (to win a title)," he said.

"Now the Australian Open, it's a tough one to answer because it is my big first tournament back."

Federer conceded that his expectations are lower, even if he has recovered well from his Hopman Cup hitout.

"I feel like as long as I'm healthy I'm going to have a shot at doing something here."