Roger Federer has shrugged off sickness to book his place in the Brisbane International quarter-finals and assured he is fit enough to defend his crown despite rumours to the contrary.

The Swiss maestro and current world No.3 got his 2016 campaign off to the ideal start, making light work of German qualifier Tobias Kamke in a 6-2 6-1 victory at Pat Rafter Arena on Thursday night.

Wrapping up the win in less than an hour, top seed Federer showed no sign of injury or ailment against the world’s 233rd-ranked player, who could do little to counter the 17-time grand slam winner’s irresistible poise and power.

But if the 34-year-old was a little sluggish, it was because of a flu-like illness he contracted off his family in the days leading up to the tournament.

The talk of the Queensland Tennis Centre on Thursday was that Federer was under a possible injury cloud, having scrapped one practice session and mysteriously cut short another – the last thing organisers of the Brisbane event wanted to hear after a spate of injuries to high-profile players.

However, Federer told reporters he never seriously considered pulling the pin and is on his way back to full fitness.

“The way I started to feel late last night and today, with the speed of the court and all that, I felt like I’m happy to give it a go,” he said.

“I guess I got some kind of flu. My whole family had it.

“I was the last guy to get it, so I knew what I was getting into when I was not feeling well.”

Federer, who had a bye in the first round, said he asked tournament organisers for a Thursday start to give him extra time to overcome his illness.

“I know they can do (that) very easily, which was helpful,” he said.

“So (I) started to feel a little bit better. That’s why I came out (on Wednesday) for a hit, just to see how things are. I was happy.

“There was no need to push it at all. I am not somebody that needs to play much before matches.”

Even so, Federer said he was “quite surprised” he went so well against Kamke, with the win setting up a quarter-final showdown with the man once dubbed ‘Baby Fed’, Bulgaria’s Grigor Dimitrov.

It is a rematch of last year’s Brisbane semi-final, in which Federer prevailed in straight sets before beating Canada’s Milos Raonic in the final.