Roger Federer does not do breakfast here at the Australian Open. The world No 2, who has played his last four matches at night, has not been getting to bed before 3am and then sleeps through the morning.
"In some ways I'd rather have the day session because that creates a normal rhythm and a normal life," Federer said. "Going to bed at three in the morning and getting up at noon is not what you're supposed to be doing. But I'm happy to do it."
Federer, who meets Andy Murray in the semi-finals today, has a remarkable fitness record and usually recovers well after matches. However, it remains to be seen how much his five-set quarter-final against Jo-Wilfried Tsonga on Wednesday night, which lasted three hours and 34 minutes, took out of him.
Darren Cahill, the highly respected former coach of Andre Agassi and Lleyton Hewitt who is working here as a broadcaster for ESPN, said: "I think physically that five-set match with Tsonga was reasonably taxing. While it wasn't that long a match it was the same sort of style of match that Roger plays. There are five-set matches you can play for four hours and physically you feel OK. There are five-set matches that last three and a half hours and you feel like you've hit the wall.
"That was one of those matches because Tsonga's so explosive in his movement Roger couldn't settle into any type of pattern and he had to do a ton of running as well. How he feels physically will maybe determine how aggressively he comes out at the start, but I think you'll see someone that's going to take the game to Andy."
Murray has won all his matches here in straight sets. Federer, who has had a tough draw, admitted he would rather have been in Murray's shoes, though he said there were positives to take out of his win over Tsonga.
"I toughed it out," Federer said. "That also gives you confidence when you have to go through those matches. The physical stamina was there, the focus was there until the very end, so it does give you a lot of confidence moving forward. I didn't play any lead-up tournaments, so that's exactly maybe what I needed for the semis. Then again, I may be totally wrong. Time will tell."
Cahill, who worked with Murray when he was between coaches and introduced him to Ivan Lendl, has been impressed by the Scot's "great progress" over the last 12 months, though he believes that Federer also played his part in making him a more aggressive and more effective player.
"I can remember four or five years ago that Roger was saying Andy's counter-punching style wasn't going to get him over that hurdle," Cahill said. "The fact that he's playing more aggressively is taking what Roger said on board –and to me he's a better player now than he was four or five years ago."
Asked what he expected from today's semi-final, Cahill said: "Those couple of big wins Andy had at the US Open and the Olympics will serve him really well in those particular moments. Again playing Roger is a completely different thing and you can't put your finger on what is eventually going to help him get over that hurdle in a Slam. I think he's 0-3 against him in majors. It's a factor, but I'm not sure how big a factor.
"I think the Olympics went some way to erasing that, but in the end Roger is incredibly difficult to beat in majors and until you do it there's always going to be that small element of doubt in your mind. But it looks like Andy has prepared as well as he can, he's playing exceptionally well, and if he's going to do it, it's probably as good a time as any."