Novak Djokovic dropped a set for the second match running but survived a tough examination by 15th seed Daniil Medvedev yesterday to reach the Australian Open quarter-finals.

The World No. 1 won 6-4, 6-7 (5/7), 6-2, 6-3 and will face Japan's eighth seed Kei Nishikori for a place in the semi-finals. Djokovic and Medvedev both needed attention from the trainer during a draining 3hr 15min match liberally sprinkled with punishing rallies of 30 shots or more, and one of 42 strokes.