Defending champion Jannik Sinner has moved into the quarterfinals at the Australian Open after beating Holger Rune during a match slowed down by medical timeouts for each player and a delay because the net got knocked loose.

The World No. 1, despite feeling unwell in sweltering conditions, kept up his title defense with a four-set triumph.

The defending champion moved into the quarterfinals at Melbourne Park on Monday by eliminating the 13th-seeded Rune 6-3, 3-6, 6-3, 6-2.