Defending champion Jannik Sinner came through a tough physical battle against Holger Rune to reach the Australian Open quarter-finals.
In a match disrupted by medical timeouts and a broken net, both Sinner and Rune seemed to struggle with the 32C heat on Rod Laver Arena.
Sinner, towards the end of the second set and into the third, was visibly shaking during the changeovers as he wrapped ice towels around his neck.
But the world number one prevailed to win 6-3 3-6 6-3 6-2 against the Dane.
"I knew in my mind even before the match I would struggle today," Sinner, 23, said
"This morning was a very strange morning because I didn't even warm up today, trying to go on court as fit as I could."
