With the Australian Open rapidly approaching, Roger Federer has admitted he is struggling for fitness.
The world number three has been struggling with flu while competing at the Brisbane International, but booked his place in the semi-finals on Friday with a 6-4-6-7 (4-7) 6-4 triumph over Grigor Dimitrov.
Although the Swiss moved a step closer to defending the title he won in 2015, he disclosed he does not feel in peak condition as he prepares to win his first grand slam since 2012 at the Australian Open.
"I'm not going to tell you too much, but it was tough in a way," Federer said. "The body is not quite ready, you know, so it's good to get through without any issues.
"I thought I played really well considering [the situation] and caught sort of a second wind in the third set.
"[The] end of the second was tough - also the beginning. I had to focus hard, so I thought I was able to relax again midway or at the beginning of the third set at some stage.
"Physically, it was difficult. Thankfully I didn't carry anything over from the first match."
Federer will now face Dominic Thiem, who eliminated Marin Cilic, in the final four.