The grim expression across Jannik Sinner’s face as he limped gingerly to the bathroom said enough. As play was briefly suspended in the overbearing Melbourne heat, the two-time defending champion was suffering from full-body cramps and at serious risk of also enduring one of the great Australian Open upsets.
The second seed survived thanks to the combined force of his mental toughness and a significant amount of luck, holding off a spirited challenge from Eliot Spizzirri to reach the fourth round with a 4-6, 6-3, 6-4, 6-4 win.
The straightforward scores in the final three sets belie the drama that unfolded on Rod Laver Arena. On the hottest day of the tournament so far, Sinner struggled in 36C heat against Spizzirri, a 24-year-old American ranked No 85 and in the main draw of a grand slam for just the third time.
Early in set three, Sinner began to cramp and fell down a break as he struggled to walk. At the exact moment Sinner looked in trouble, however, the Australian Open’s extreme heat rules came into effect, forcing the closure of the roof and an opportunity for the Italian to recover and advance.
It took an immense mental effort for Sinner to turn the match around, but without the perfectly timed stoppage his title defence could have easily come to an end. “I struggled physically a bit today,” said Sinner. “I got lucky with the heat rule, they closed the roof. I took my time, as the time passed, I felt better. I’m very happy with this performance.”
Sinner initially appeared to be cruising through the early stages, establishing a 4-2 lead. But he quickly unravelled in suffocating conditions while Spizzirri looked comfortable. By the end of the set, Sinner was struggling between points and the American was rewarded for his composed, consistent offensive play with a 6-4 win.
After being down an early break in set two, Sinner recovered well enough to level the match but he never looked comfortable. His body was in full revolt at the beginning of set three as he cramped in both legs and arms. Unable to properly run, Sinner called the trainer while trailing 1-2 in the third set.
The Australian Open’s heat rules are dictated by the tournament’s Heat Stress Scale, a chart that rates the playing conditions between 1 and 5, with 1 meaning “temperate playing conditions” and 5 immediately leading to the suspension of play. The heat stress reading, which had been rising steadily all afternoon, hit 5 exactly as Spizzirri broke a hobbled Sinner’s serve to lead 3-1.
Play stopped and the roof was closed. Sinner used the break to head to the bathroom, hobbling off the court with a significant limp. His movement was still diminished on his return but he immediately got to work in cool conditions under the roof, retrieving the break with relentless first-strike tennis.
Men's singles
(1) Carlos Alcaraz v Tommy Paul (19)
(10) Alexander Bublik v Alex de Minaur (6)
(3) Alexander Zverev v Francisco Cerundolo (18)
(11) Daniil Medvedev v Learner Tien (25)
(5) Lorenzo Musetti v Taylor Fritz (9)
(16) Jakub Mensik v Novak Djokovic (4)
(8) Ben Shelton v Casper Ruud (12)
(22) Luciano Darderi v Jannik Sinner (2)
Women's singles
(1) Aryna Sabalenka v Victoria Mboko (17)
Yulia Putintseva v Iva Jovic (29)
(3) Coco Gauff v Karolina Muchova (19)
(12) Elina Svitolina v Mirra Andreeva (8)
(6) Jessica Pegula v Madison Keys (9)
Wang Xinyu v Amanda Anisimova (4)
(5) Elena Rybakina v Elise Mertens (21)
Madison Inglis v Iga Swiatek (2)
Sunday's order of play (singles only)
Rod Laver Arena
Day: Sabalenka v Mboko, Alcaraz v Paul
Night: Bublik v De Minaur, Svitolina v Andreeva
Margaret Court Arena
Day: Gauff v Muchova, Medvedev v Tien
John Cain Arena
Day: Putintsteva v Jovic, Zverev v Cerundolo
Sinner opted not to sit during most changeovers for the rest of the match to ensure that the cramps did not return but the cooler conditions under the roof allowed him to gradually improve physically. Sinner slowly took control of the match and held on to secure his position in the last 16.
Despite his dominant results in recent years, extreme heat remains Sinner’s weakness. The 24-year-old’s only defeat on hard court since September 2024 to any player other than Carlos Alcaraz was a retirement loss to Tallon Griekspoor in extreme heat and humidity at the Shanghai Open last October.
In Melbourne last year, struggling badly with illness in tough conditions against Holger Rune in their fourth round match, he similarly dragged himself through. These struggles have often strengthened Sinner and propelled him to success. He will be even more dangerous and determined in the battles ahead.
Elsewhere, Stan Wawrinka put up a valiant fight in his final match at the Australian Open before falling 7-6 (5), 2-6, 6-4, 6-4 to the ninth seed Taylor Fritz in the third round. At 40 years old, Wawrinka had become the oldest man in 48 years to reach the third round of the Australian Open after a dramatic five set win against Arthur Gea of France. Although he had his chances in the opening set and he was competitive for nearly three hours against a top 10 player, Wawrinka was eventually outplayed by a solid Fritz.
After the match, the 2014 champion received an emotional on-court farewell ceremony hosted by tournament director Craig Tiley. He later declared himself ecstatic with his level at the beginning of his final year as a professional tennis player.
“This for me was a great two weeks, three weeks now, between here and the United Cup,” he said. “The level was great. I can see that I’m competitive, that I’m feeling good on the court, that I can win some good matches, play against the top players. It’s exactly what I’m looking for.
“Doesn’t change my goal for the year. It’s always going to be to push my limit. It’s not because I play well those three weeks that I’m going to win a lot of matches in the next few months, but at least I know where my level is and what I can still do, and I’m happy with that.”
Iga Swiatek recovered from a brief second set hiccup to keep her hopes of winning the career grand slam alive with a 6-1, 1-6, 6-1 win over Anna Kalinskaya on Saturday night. Madison Keys, meanwhile, continue her title defence alive with a comfortable 6-3, 6-3 win over the former No 1 Karolina Pliskova.
