Jannik Sinner survives heat to reach Australian Open fourth round

The two-time defending champion and No. 2 seed was visibly struggling as extreme heat took its toll, experiencing cramps in both his arms and legs and limping badly as his movement became increasingly restricted.

Sinner fell behind 3-1 in the third set and had gone down a break when play was halted under the tournament's extreme heat policy. The roof was closed and a brief suspension followed, before a 10-minute cooling break was later permitted between the third and fourth sets.

At one stage, the 24-year-old Italian appeared close to elimination, but coach Darren Cahill urged him to persevere for a few more games. Sinner later admitted he was simply trying to survive until a longer break.

The interruption proved decisive, with conditions improving as glare reduced, temperatures eased and radiated heat from the court dropped noticeably.

Revitalised, Sinner won five of the next six games to take the third set and eventually closed out a 4-6, 6-3, 6-4, 6-4 victory over world No. 85 Eliot Spizzirri.

The American, also 24, was making his main-draw debut and earned early crowd support, converting six of 16 break points and breaking Sinner's serve more often than any opponent in Melbourne since the 2024 final against Daniil Medvedev.

Despite receiving a rare time violation from umpire Fergus Murphy - overturned after Spizzirri's show of sportsmanship - Sinner regained confidence as the match wore on.

"I struggled physically today. I got lucky with the heat rule," said Sinner.

"As the time passed, I felt better and better. It started with the legs. Got to the arms. I was cramping a bit all over.

"This is the sport. This is an area I know I need to improve. Tennis is a very mental game. I tried to stay as calm as possible. I'm here to fight, to play every point the best possible way."

He will next face fellow Italian Luciano Darderi, who defeated No. 15 seed Karen Khachanov in four sets.

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