MELBOURNE (AFP) - World number one Novak Djokovic fought off Gilles Muller to reach his eighth consecutive quarter-final at the Australian Open on Monday.

The four-time champion did not have his service broken as he beat the 42nd-ranked Muller from Luxembourg 6-4, 7-5, 7-5 and will play Milos Raonic for a place in the semi-finals.

Raonic, the eighth seed, had earlier created history when he became the first Canadian man to reach the Australian Open quarter-finals in 47 years with a five-set win over Feliciano Lopez.

The big-serving 24-year-old's 6-4, 4-6, 6-3, 6-7 (7/9) 6-3 win in 3 hours 5 mins equalled Michale Belkin's feat in 1968.

"It's great to be doing what I'm doing and that it is making a difference," Raonic said.

"It is, I guess, part of some history, if you look really deep. But at the end of the day, at the same time, I'm always pushing myself for what I want to achieve."