The Spaniard is chasing his 15th grand slam success, with Federer's 17 still in sight.
The atmosphere is sure to be incredible on Rod Laver Arena, but it is unlikely either Nadal or Federer will concern themselves with exterior pressure given the number of times they have appeared together in such crucial matches.
If the quality is anywhere near as high as the tennis on show today, then the fans will be just happy too. The latter played out of his skin and lived up to his reputation as "baby Roger Federer". And given how Rafa and Roger have played throughout this tournament, using their guile, skills and experience to best younger players, it will be one cracker of an Australian Open final.
Both had been written off in the past couple of years.
Either Federer, 35, will expand his record haul of major singles titles with his 18th, or 30-year-old Nadal will close the gap on the Swiss legend by winning his 15th.
The overall numbers are common knowledge, but there's also the narrative within matches that has increasingly been going against Federer in the last few years. Then everything happened to him, body breaking down, image breaking down, marriage breaking down.
By the time the French Open comes round in May, chances are that Murray and Djokovic will be into their stride and it will be harder to look past them for the last three Grand Slams. The difference was the number of times Nadal converted those chances - 101 times, compared to Federer's 83.
Nadal, 20, successfully defended his French Open title and established his reputation as the world's best player on clay.
It took just under five hours for the world No. 9 to defeat world No. 15 Dimitrov 6-3, 5-7, 7-6 (5), 6-7 (4), 6-4, a match where the level of tennis was "just brutal in terms of physical performance" ensuring neither opponent was giving the other easy points.
Nadal completed the 30-plus quartet in a match that started in local prime time Friday and finished at 12:45 a.m. Dimitrov, who had only beaten Nadal once in eight previous matches and was in a Grand Slam semifinal for only the second time, played the match of his life. Nadal emerged victorious in the deciding set 6-2 to prevent Federer from equalling Pete Sampras' record of 14 Grand Slam titles.
Hlavackova and Peng, who had not dropped a set on the way to the final, took an early service break and seemed in command of the opening set.
The last time both men's semi-finals went to five sets at any Slam was at 2009 Roland Garros, when Federer beat Juan Martin del Potro and Robin Soderling defeated Fernando Gonzalez.
No player loves a scrap more than Nadal and he hung on for the toughest of holds, in which Melbourne Park marvelled at his ability to lift in the big moments. "I know this court allows me to play a certain game against Rafa that I can not do on centre court at the French Open".
If there were any doubts over Rafa, they were crushed in his five-hour marathon win over Grigor Dimitrov in the semis. "Most of my fight and courage I've gotten from Venus".
"It's special, we have not been there in that situation for a while, so that makes the match different".
"It's not something I'm necessarily really anxious about in any way".
"It was a moment we never thought we were ever going to have again, to be in the final in Australia, so we both feel very happy".