Jannik Sinner fought through dizziness and an unusual interruption to reach the quarter-finals of the 2025 Australian Open, where he will face Alex de Minaur. The defending champion triumphed 6-3, 3-6, 6-3, 6-2 over Denmark’s 13th seed Holger Rune on Monday, despite struggling with physical issues on the court.

Sinner, visibly affected by the hot Melbourne conditions, admitted he was feeling unwell, with shaking hands and a raised heart rate during the third set. He took a medical timeout before a bizarre 20-minute delay when he accidentally broke the net with a powerful serve early in the fourth set.

“I wasn’t feeling really well. I was struggling physically, and I was a bit dizzy at times,” said the 23-year-old Italian. "I was lucky today with the time off court to cool down and refresh, putting cold water on my head. It was big luck."

The break allowed Sinner to reset physically, and he returned to break Rune’s serve in the fourth set, securing a dominant win to set up a showdown with Australia’s Alex de Minaur.

De Minaur, who has reached his first Australian Open quarter-final, defeated American Alex Michelsen 6-0, 7-6 (7/5), 6-3 in his fourth-round match.

Sinner, aiming to become the first Italian man to win three Grand Slam titles, had dropped just one set prior to this match and maintained his serve under pressure. Rune broke back in the second set with a key Sinner double fault, but the world number one regained control in the third and fourth sets after his brief break.

With this victory, Sinner will look to defend his Australian Open crown, having defeated Daniil Medvedev in last year’s final. The upcoming clash against De Minaur promises to be a thrilling contest as both players fight for a spot in the semifinals.