Rafael Nadal looked in ominous form in a crushing win over Damir Dzumhur to reach the fourth round of the Australian Open.

Playing in much cooler conditions than those which greeted the daytime matches, Nadal took an hour and 50 minutes to overcome Bosnian 28th seed Damir Dzumhur 6-1 6-3 6-1.

Last year’s runner-up, who plays 24th seed Diego Schwartzman next, has yet to drop a set and has put concern about the state of his knees firmly behind him.

Things were tougher for third seed Grigor Dimitrov, the man Nadal beat in an epic semi-final 12 months ago.

Dimitrov has yet to find the form that carried him to the brink of a first grand slam final but there is no doubt about his desire and he battled past 30th seed Andrey Rublev 6-3 4-6 6-4 6-4.

The Bulgarian was taken to five sets by American qualifier Mackenzie McDonald in the previous round and was at least happy that he is heading in the right direction.

Dimitrov said:  “I recovered well. Obviously today was another tough test for me. I just had to find a way again, simple as that. At least the game was a little bit better than the previous match.”

While other players struggled to adapt to the conditions, with the temperature topping 40C, Dimitrov found them just to his liking.

He said: “I love being out in the heat. That doesn’t scare me at all. Back in Bulgaria when I was a kid growing up, the summers were pretty hot and dry. I felt like almost home today. The conditions were great.”

Dimitrov and Rublev served a remarkable 28 double faults between them, with the Bulgarian throwing in 15. “That’s absolutely unacceptable,” he said. “Hopefully I serve better next round.”

Unseeded players Kyle Edmund and Andreas Seppi will clash for a place in the quarter-finals after both survived five-set encounters.

Edmund played through the hottest period of the day and fought from two sets to one down to beat Nikoloz Basilashvili 7-6 (7/0) 3-6 4-6 6-0 7-5 while Seppi withstood an Ivo Karlovic comeback, beating the 6ft 11in Croatian 6-3 7-6 (7/4) 6-7 (3/7) 6-7 (5/7) 9-7.