Novak Djokovic advanced to his sixth Australian Open final with a 6-1 6-2 3-6 6-3 victory over Roger Federer.

The world number one dominated the first two sets with some superb hitting, then had to hold off a spirited Federer fightback.

It is the third straight Grand Slam in which Djokovic has beaten the Swiss, prolonging Federer's wait for an 18th major title.

Djokovic will face Andy Murray or Canada's Milos Raonic in the final.

The Serb has beaten British number one Murray in the final on three previous occasions, including last year's four-set victory.

"I played unbelievably in the first two sets but I needed to because Roger has been playing unbelievably and I knew he would be aggressive," 10-time Grand Slam winner Djokovic said.

But just when a Djokovic victory seemed inevitable, somehow Federer managed to reverse the momentum of the match to take the third set.

The 34-year-old held his opening three service games then seized his opportunity in a mammoth sixth game, missing three break points before finally breaking Djokovic at the fourth opportunity.

The fourth set was closely contested as a resurgent Federer threatened to extend Djokovic to five sets for the first time since their epic meeting in the 2014 Wimbledon final.

But a poor game at 3-4 ultimately proved costly as Djokovic broke and then served out to love to edge ahead 23-22 in his rivalry with Federer.

"My rhythm, my timing, all that, was a bit off in the beginning," said Federer. "He took advantage of that and did an unbelievable job for a long, long time tonight."