MELBOURNE, Jan 21 — American 12th seed Taylor Fritz dumped last year’s Australian Open runner-up Stefanos Tsitsipas out of the tournament on Sunday to set up a quarter-final with defending champion Novak Djokovic.

There was little to separate them in the opening two sets but Fritz stepped up a gear to beat the Greek seventh seed 7-6 (7/3), 5-7, 6-3, 6-3 in a shade over three hours.

He said the key was "just trusting my shots” and that he had served well throughout.

Fritz trails Djokovic 8-0 in head-to-heads, but he said he had improved and was relishing another battle against the top seed.

"The times I have played him I haven’t brought my best level and you need to if you are going to complete with someone like Djokovic,” he said.

A tight first set, in which neither player broke serve, went to a tie-break, where Fritz quickly edged ahead and did not relinquish his lead.

The second set went with serve until the 11th game, when Tsitsipas broke, going on to take the set 7-5.

Fritz broke twice in the third set to edge ahead and repeated the feat in the fourth set, winning the last four games to claim victory. — AFP