Jannik Sinner’s hopes of a third successive Australian Open title were saved by the heat rule as the second seed fought off cramp and American Eliot Spizzirri to reach the fourth round.
The Italian was in big trouble early in the third set on Rod Laver Arena as his legs seized up but, at the same moment, the tournament’s heat stress scale hit five, triggering the closing of the roof.
Sinner continued to look uncomfortable but, out of the punishing sun and with air conditioning cooling the arena, he battled to a 4-6 6-3 6-4 6-4 victory.
“I struggled physically a bit today,” said the relieved second seed. “I got lucky with the heat rule and the roof closing. I took my time and as the time passed I felt better and better.
“I’m very happy about this performance. Looking back at every big tournament there were some tough matches. Hopefully this can give me some positives for the next round.”
While Sinner was ultimately fortunate with the timing, he could consider himself somewhat hard done by to be scheduled second on, with temperatures climbing rapidly during the early afternoon.
Organisers had pushed the start of play on the main courts forward by an hour with extreme heat forecast of up to 40 degrees for the first time this fortnight, meaning the Italian took to Rod Laver Arena just after midday.
Sinner is known to find such conditions difficult – last year here his only struggle came in the fourth round against Holger Rune when it was hot, while his last defeat, in Shanghai in October, saw him retire with cramp against Tallon Griekspoor.
Against Spizzirri, a 24-year-old debutant ranked 85, Sinner’s initial problems were with his own game, the four-time grand slam champion making a host of unexpected errors and losing five games in a row to trail by a set and a break.
He steadied and had levelled the match when it became clear his body was beginning to really feel the heat.
Sinner called the trainer after three games of the third set to have his right calf massaged but in the next game at deuce he became racked by cramp and Spizzirri broke to lead 3-1.
At the same moment, the heat stress scale – which measures air temperature, radiant heat, humidity and wind speed – ticked from 4.9 to five, providing relief for Sinner and prompting a wry smile from Spizzirri.
“I started with the leg, then it got into the arm,” said Sinner. “I was cramping a bit all over.
“This is the sport, I know this is an area where I need to improve. Tennis is a very mental game, I just tried to stay as calm as possible. I’m here to fight.”
Things were not straightforward thereafter but Sinner hit back immediately on the resumption and a costly double fault from Spizzirri gave his opponent the key break for 5-4.
A 10-minute stoppage after the third set as part of the tournament’s heat protocols gave Sinner more chance to recover and his movement finally began to improve late in the fourth set as he fought back from 3-1 down to claim victory.
Sinner will next face compatriot Luciano Darderi, with three Italian men through to the last 16 here for the first time.
Fifth seed Lorenzo Musetti coped with the heat a lot better than Sinner, battling to a 5-7 6-4 6-2 5-7 6-2 victory over Tomas Machac after four hours and 27 minutes.
Play was suspended completely on matches without roofs just after 2.30pm.
That came too late, though, for British 16-year-old Hollie Smart, who retired in tears from her first-round match in the girls’ singles leading Japan’s Azuna Ichioka 7-5 6-7 (7) 3-2 after becoming completely racked with cramp.
Smart was attended to by medics for several minutes after the match, with ice placed on her body, and she was then able to walk off court.
