Defending Australian Open champion Novak Djokovic booked his place in the quarter-finals of a Grand Slam event for the 27th time in a row in Melbourne this morning.

However, the world number one was pushed all the way by Gilles Simon, who forced Djokovic to make 100 errors before he ultimately won through in five sets 6-3 6-7(1) 6-4 4-6 6-3.

The two players traded the opening four sets evenly, but it was Djokovic that took control of the fifth and final set to secure his victory in four hours and 32 minutes on court.

Ahead of his meeting with Kei Nishikori in the last eight, the Serb said: "Hopefully I will be able to decrease my unforced error stats compared to the match that I've had today. Hopefully I'll be able to do that and perform my best."

Djokovic is a five-time champion at Melbourne Park, having triumphed in 2008, 2011, 2012, 2013 and 12 months ago.