World No 1 Rafael Nadal will play Roger Federer for the 33rd time when they go head-to-head in Friday's blockbuster semi-final at the Australian Open.
The Spaniard leads their overall meetings by 22-10 and Federer has not beaten his nemesis at a major since the Wimbledon final of 2007.
However, 17-time Grand Slam champion has been like a man reborn. A combination of Federer's resurgence under new coach Stefan Edberg, and Nadal's blister-induced weakened serve, has thrown open the outcome of this mouthwatering contest.
Nadal, a 13-time Grand Slam champion, was clearly discomfited by the ugly blister as he spluttered with seven double-faults, two on break points, in his battling four-set win over Grigor Dimitrov in the quarter-finals and only the Swiss great now stands in the way of a third Australian Open final appearance.
He is bidding to become only the third man to win each of the four Grand Slam titles twice should he get through to Sunday's final against Stanislas Wawrinka but conceded the strapping on his blister is badly affecting his serve.
"I feel that with the tape I can lose the racquet when I'm serving," said Nadal. "That's a terrible feeling for a serve.
"I'm going to try to improve. If not, I'm not going to have the chance to be in the final."
Meanwhile, former world No 1 Federer, now ranked sixth, has looked back to something like his best form thanks to his larger-headed racquet and Edberg in his corner to advise him.
Wins over Jo-Wilfried Tsonga and triple runner-up Andy Murray which took him through to the last four Down Under for an 11th consecutive time.
The 32-year-old was able to train fully during the off season and his renewed confidence has been shining through round after round with attacking tennis reminiscent of his glory years.
He will now be looking to reach his first Grand Slam final since beating Andy Murray to win Wimbledon in 2012 and there is also the tantalising possibility of an all-Swiss final, with Wawrinka.
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."
In the day's other matches, sixth-seeded Sania Mirza and Horia Tecau take on home favourites Jarmila Gajdosova and Matthew Ebden on Rod Laver Arena while over on Margaret Court, China's Jie Zheng and American Scott Lipsky face Wimbledon champions Kristina Mladenovic and Daniel Nestor in the mixed-doubles semi-finals.
Also, in the first of the women's doubles semi-finals top-seeded Sara Errani and Roberta Vinci from Italy battle Russia's Ekaterina Makarova and Elena Vesnina on Rod Laver before the main event.
Ahead of their Australian Open semi-final, we look back at some of the best Nadal v Federer matches.