A few minutes after Andy Murray finished off a routine, professional victory over Jeremy Chardy here yesterday to reach his 12th grand slam semi-final, the Scot expressed a sly wish that Roger Federer and Jo-Wilfried Tsonga would go hammer and tongs with each other in the night match.

It was said with a smile on his face but as the quarter-final between Federer and Tsonga went into a fifth set, it would surely have widened into a grin. Federer eventually came through to set up a mouthwatering semi-final with Murray tomorrow night but the US Open champion would have gone to bed knowing he, at least, will be fresh.

In reaching the semi-finals, Murray has not dropped a set – the only other time he did that in a grand slam was here three years ago – and he has spent a total of 8 hours 55 minutes on court.

That compares favourably to Federer, who has been on court 10 hours 47 minutes and even more so compared to world No.1 Novak Djokovic (13 hours 6 minutes) and David Ferrer (12 hours 19 minutes). Djokovic and Ferrer were due to play each other this morning, UK time, in what is a repeat of last year's US Open semi-final and what could easily be another gruelling encounter.

Murray will take nothing for granted against Federer, a man he leads 10-9 in their previous meetings but who made him cry in the last two grand slam finals they contested; last year's Wimbledon and the final here in 2010.

The big thing for the Scot, though, is that having lost the Wimbledon final in July, he bounced back immediately by beating the Swiss handsomely to win the gold medal in the Olympics, back on the grass again at the All England Club.

As Federer said, after his 7-6, 4-6, 7-6, 3-6, 6-3 victory over Tsonga, Murray has now "got the monkey off his back" and is playing more aggressively.

"I know what to expect," Federer said. "He has changed his game around a bit. He's playing more offensive. I'm looking forward to it. Obviously, he is a great player and I was very happy for him when he won his first grand slam title and the gold medal [at the Olympics]."

Murray produced his best tennis of the week to destroy any hopes world No.37 Chardy had of causing an upset. The Frenchman hit back from 4-0 down to make a fist of the first set but Murray was at his concentrated best and never allowed him a sniff as he won 6-4, 6-1, 6-2.

Since hiring Ivan Lendl as his coach just more than a year ago, Murray has made much of his new-found calmness on court and said that winning the US Open had also relaxed him further.

"I probably feel a little bit calmer than usual," Murray said. "But I still have an understanding of how difficult it is to win these events. With the players that are still left in the tournament, it's going to be a very tough few days if I want to do that.

"So I'll just stay focused, work hard in my next couple of practice sessions and hope that I can finish the tournament well."

Murray may be at a slight disadvantage going into the semi-final having not played at night yet this fortnight while Federer has experienced life under the lights four times out of five.

But the Scot is more mature these days, more able to handle any such mini-setbacks and last night he went out to the Hisense Arena, the second biggest court at Melbourne Park, to get a feel for the cooler conditions.

Much has also been made of the fact that he has yet to be pushed hard in a match. Federer said he would rather be in Murray's position and the Scot said he had to believe in his ability when he is called on to dig a little bit deeper.

"I think you have to trust yourself that when you are tested, you're going to play better tennis," he said. "You never know for sure but in the build-up to the tournament, I played very well.

"I haven't lost a set here yet. So maybe I'm expecting to play too well or whatever. I've done a good job so far in this tournament. I can't be disappointed with where my game's at.

"I played a lot of tennis in December. I had some good matches in Brisbane [where he won the title]. So I can't be disappointed about being in the semis of a slam without dropping a set. That would be silly."

Federer, who is trying to extend his record grand slam tally to 18, said he was looking forward to the challenge of playing Murray, having beaten him here in the final three years ago.

"I've always enjoyed the match-ups with him because it gets to be very tactical," he said. "It wasn't a straight-forward match. He would make you doubt and play very different to the rest of the guys. I've always enjoyed that.

"Now, it's changed a bit because he's playing more offensive. The rallies aren't as long and gruelling as they used to be. We both can do that.

"But I've made it into the semis, which I'm very pleased with. It's not going to get any easier from here. I'm excited that I'm in the semis and that's what I'm supposed to be, so I'm looking forward to it."