World number one Novak Djokovic reached the Australian Open quarter-finals for the first time since 2016 with a hard-fought win over Daniil Medvedev.

The 31-year-old Serb earned a 6-4 6-7 (5-7) 6-2 6-3 victory over the 15th seed in Melbourne.

Djokovic was not at his fluent best, but outlasted Medvedev to win in three hours and 15 minutes.

Russia’s Medvedev, 22, grew frustrated as he paid the price for only taking two of nine break points.

Medvedev’s resistance continued until the end, saving two match points before Djokovic took the third with a wonderful cross-court winner.

Six-time champion Djokovic will play Kei Nishikori in the last eight after the Japanese eighth seed beat Spain’s Pablo Carreno Busta in controversial circumstances in a five-hour match decided by a super tie-break.

Another triumph for the top seed at Melbourne Park will see him move ahead of Australian great Roy Emerson and Roger Federer, who was knocked out by Greek youngster Stefanos Tsitsipas on Sunday, in terms of all-time victories.

Djokovic outlasts Medvedev in physical encounter

Djokovic’s progress to the last 16 had been relatively serene, apart from a third-set blip which came against the run of play in his previous win over Canadian teenager Denis Shapovalov.

But the powerful Medvedev, one of the rising stars and in good form having reached the final at the Brisbane International coming into the tournament, was expected to provide a sterner test.

It was a test of durability as the pair pushed each other in some long, physical rallies – including two which lasted more than 40 shots.

In stuffy conditions on Rod Laver Arena, both players struggled physically at times with Medvedev appearing to tire first in the third set.

Although there was a suspicion Medvedev was putting up little fight to preserve energy for a push in the fourth, it proved to be the key to Djokovic’s victory as he maintained the momentum that had swung his way.

“It was definitely a physical battle,” Djokovic said.

“It is difficult to go through him and I had to find another way to go through him.

“In this kind of match you just have to hang in there and wait for your opportunities.”

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