An unstoppable Roger Federer has advanced to his seventh Australian Open final, with unseeded South Korean opponent Hyeon Chung retiring hurt during their semi-final.

Federer had conceded just one game on Friday night when Chung, who struggled with a blister on his left foot, shook the umpire’s hand with the Swiss maestro ahead 6-1 5-2.

The 19-time grand slam winner will face Croatia’s Marin Cilic in Sunday night’s title decider.