Defending champion Novak Djokovic survived a scare against Gilles Simon to reach the last eight of the Australian Open in Melbourne.

Five-time champion Djokovic made 100 unforced errors but prevailed 6-3 6-7 6-4 4-6 6-3 after four hours and 32 minutes on Rod Laver Arena.

Djokovic, is through to his 27th consecutive Grand Slam quarter-final.

The Serb plays Japan's Kei Nishikori in the last eight after the seventh seed beat Jo-Wilfried Tsonga 6-4 6-2 6-4.