ROGER Federer is dreaming of grand slam titles again but first he must get past his old rival Rafael Nadal.
The 17-time grand slam champion came into the Australian Open as an outsider after his 2013 struggles but has looked back to something like his best form in wins over Andy Murray and Jo-Wilfried Tsonga.
Having lost to Murray in the semi-finals 12 months ago, Federer took revenge yesterday to reach the last four in Melbourne for an 11th consecutive time.
The 32-year-old has not made a grand slam final since winning the last of his titles with victory over Murray at Wimbledon in 2012.
He has beaten Nadal only 10 times in 32 meetings, and not at a slam since the Wimbledon final of 2007, but the Spaniard is struggling with a blister on the palm of his left hand and battled past Grigor Dimitrov in his quarter-final.
For Federer, meanwhile, there is also the tantalising possibility of an all-Swiss final, with Stanislas Wawrinka facing Czech Tomas Berdych after his stunning upset of Novak Djokovic.
"For me it's an amazing result to be in the semis," said Federer.
"This one feels different because of the tougher times I've had in the slams.
"Plus what I really love is another Swiss is in the semis as well. It's the first time in history.
"So that's a big deal. I didn't think about it all the time when I was playing, but it was definitely inspiring tennis by him.
"For me, it's a dream run, and I hope I can keep it up against Rafa.
"Clearly when you're in the semis, you start dreaming. There's no doubt about that."
Federer will hope the changes he has made can bring about a change of fortune against Nadal.
The Swiss is playing with a larger-headed racquet and has Stefan Edberg in his corner along with regular coach Severin Luthi.
Edberg has already won the battle of the super coaches, with Murray's mentor Ivan Lendl and Djokovic's new head coach Boris Becker both heading home.
Federer will face Nadal at a slam for the first time since the semi-finals here two years ago, and he said: "He's been tough to play against, no doubt. I'm happy I get a chance to play him in a slam again.
"The head-to-head record is in his favour. I'm looking forward to speaking to Stefan, because when we spoke together when he came to Dubai and we spoke about the game, we clearly spoke about playing Rafa as well. He thought he had some good ideas."
Nadal had to fight back from a set down against first-time slam quarter-finalist Dimitrov and admitted he was "so lucky" not to drop the third as well.
Dimitrov had three set points and on the second he pushed a routine forehand wide, with Nadal eventually coming through 3-6 7-6 (7/3) 7-6 (9/7) 6-2.
Meanwhile, Murray was proud of his efforts in pushing Federer to four sets.
Murray said: "I gave him the break at the end of the match. That was disappointing.
"In the first two sets I thought he played great tennis. When he was serving for the match I felt like I raised my level because I had to basically, and I obviously prolonged the match a bit further.
"I just wasn't able to get ahead in the fourth set. I was proud of the way I fought.
"That's the highest level I've played at in a long time.
"My serve slowed down a bit in the fourth set, especially the first couple of points when I was getting up after the change of ends.
"But I hung in well. I pushed through it and almost got myself back in the match."
There will be a new women's champion after Victoria Azarenka joined the purge of the favourites in Melbourne.
After fourth round exits for Serena Williams and Maria Sharapova, Azarenka was toppled by Agnieszka Radwanska, the Pole winning 6-1 5-7 6-0. Radwanska faces Dominika Cibulkova in the semi-finals, while Li Na takes on 19-year-old Eugenie Bouchard.