The weather Gods came to Jannik Sinner’s rescue today, when play was serendipitously suspended for around 10 min to close the roof on all show courts, as the Heat Rule came into effect owing to the sweltering Melbourne heat. This was right at the moment when Sinner was barely able to serve or move due to cramps and a mid-match retirement was on the cards. Fortuitous for Sinner, this happened when it was 1 set all and Eliot Spizzirri, the college tennis star from the University of Texas, USA (ranked 85 in the world) was playing some scintillating tennis and had just broken Sinner in the third set to take a 3-1 lead.
While play was suspended for some time at the outside courts, play resumed in cooler conditions on the show courts with the roof closed. This crucial 10 min break helped Sinner to cool down and recover to an extent and he subsequently went on to win the match in 4 sets.
Timing too good to be true?
The timing seems too good to be true and sparks the debate of Sinner (the 2-time AO defending champion) receiving some preferential treatment from the organizers. However, this argument does not hold water as Sinner would have probably got a night match slot in the first place as the weather forecast for today was already known and no player would have desired to play during the day today. And even more pertinent is the fact this was not a judgement call. We do have an objective measure for when the heat protocol comes into effect.
Faced with heavy criticism on the inconsistency of the heat policy implementation over the years, the AO introduced the Heat Stress Scale (HSS) in 2019, which measures heat stress on a scale of 1.0 to 5.0, by taking into account four environmental variables – air temperature, radiant heat (strength of the sun), humidity and wind speed.
The rule states that when the scale hits a reading of 4.0, a 10 min cooling break is allowed in after the 3rd set in a Men’s match (after the 2nd set in a women’s match). Today’s match between Sinner and Spizzirri started when the scale reading had already hit 4.0. So even if there was no break at 3-1 during the 3rd set due to the roof closure, a 10 min cooling break was to take place at the end of the 3rd set. But there was a high chance that Sinner would not have even made it till the end of the 3rd set as he looked physically depleted at 3-1, looking at his team sitting courtside, almost given up, as the cramps had spread from his legs to his arms.
Also, even if he made it till the end of the 3rd set, the match would have continued post that in the scorching heat, which Spizzirri seemed far more likely to handle well, as he looked unfazed by it during the entire match. This was probably because Spizzirri trains in South Florida, well-accustomed to the 40+ degree Celsius conditions, also highlighting his superior conditioning. Unluckily, his physical advantage got taken away today.
Luckily for Sinner, the scale hit 5.0 at 3-1 in the 3rd set. When that happens, the rule says that no outdoor play is allowed and play on stadium courts can continue in a climate-controlled environment after the roof is closed. And typically, once the roof is closed during a match, it remains closed for the duration of the match. Factoring in all these events, I strongly believe, had the HSS not hit 5.0 today during this match, an upset was the most likely outcome. Nonetheless, it is still commendable how Sinner was able to make a comeback from those cramps.
When there’s a will, there’s a way ?
Jannik Sinner battles the heat and cramps to take the third set against Spizzirri, 6-4.@AustralianOpen | #AO26 pic.twitter.com/1wQLRwhlNs
— ATP Tour (@atptour) January 24, 2026
Sinner’s physical conditioning
Earlier I had ignored the scepticism surrounding Sinner’s physical conditioning, but a trend has emerged, indicating that while Sinner is still one the best players ever to play tennis (already), his biggest rival is his himself (his physicality)! We do remember his narrow escape during last year’s AO 4th round match against Holger Rune when he looked physically diminished with the double whammy of an illness before the match and the scorching heat during the match. The Italian had to dig deep to come out victorious in that match, conspicuously aided by a 10 min medical timeout and another fortuitous ~20 min delay at the start of the 4th set, as the metal ring affixing the bottom of the net to the court broke.
Sinner has lost more matches in the last two years due to illness/injury/cramps than to any single opponent. Well, apart from Carlos Alcaraz. The last match he lost on tour was in the Shanghai Masters to Tallon Griekspoor in the round of 32, which was due to retirement during the final set because of severe leg cramps in brutally humid conditions.
In the last two seasons of 2024 and 2025, Sinner has lost only a total of 12 matches, 6 in each season. 6 of those 12 losses have in some way been due to physical setbacks! Here’s a list of those losses:
| Year | Tournament | Round | Opponent | Remarks | |
| 1 | 2024 | Indian Wells | Semifinal | Carlos Alcaraz | NA |
| 2 | 2024 | Monte Carlo | Semifinal | Stefanos Tsitsipas | Did suffer minor leg injury and some nervous cramps |
| 3 | 2024 | Roland Garros | Semifinal | Carlos Alcaraz | Though not the main reason for loss, but suffered from hand and leg cramps during the 3rd set |
| 4 | 2024 | Wimbledon | Quarterfinal | Daniil Medvedev | Suffered severe dizziness and fatigue during the match |
| 5 | 2024 | Montreal | Quarterfinal | Andrey Rublev | Was hampered by a right hip injury |
| 6 | 2024 | Beijing | Final | Carlos Alcaraz | NA |
| 7 | 2025 | Rome Masters | Final | Carlos Alcaraz | NA |
| 8 | 2025 | Halle | Round of 16 | Alexander Bublik | NA |
| 9 | 2025 | Roland Garros | Final | Carlos Alcaraz | NA |
| 10 | 2025 | Cincinnati | Final | Carlos Alcaraz | Retirement due to illness/fever after 5 games |
| 11 | 2025 | US Open | Final | Carlos Alcaraz | NA |
| 12 | 2025 | Shanghai | Round of 32 | Tallon Griekspoor | Retirement due to leg cramps |
Leaving aside his great rival Carlos Alcaraz, what is quite evident from the above data is that no other player has beaten an uncompromised Sinner in the last two seasons, apart from Alexander Bublik, which was once, in 3 sets on grass in Halle. If you think about it, this is quite extraordinary! No wonder that Sinner has been speaking candidly about altering his game style to make it more unpredictable in order to beat one man primarily – Carlos Alcaraz. His current ball striking and movement is more than sufficient to handle any other player at the moment. But while 7 of his 12 losses have come to Alcaraz, 6 out of the 12 losses are directly correlated to his physical setbacks. This is not a small number, considering these were all at Majors or Masters 1000s.
Not just during matches, Sinner has also had some pre-tournament withdrawals, Paris Olympics 2024 being one of them, where he was forced to withdraw due to tonsilitis, missing his chance to achieve the coveted gold in Singles. He was also forced to withdraw from the Madrid Masters in 2024, prior to his quarterfinal match against Felix Auger Aliassime, due to a right hip injury. The same issue resulted in withdrawal from this home tournament – Rome Masters, thereafter.
All this might seem inconsequential in the larger scheme of things as the Italian has had stellar seasons in both 2024 and 2025, winning two Majors in each year, 4 Masters 1000s and the World Tour Finals in both years without dropping a set and also finishing world number 1 in 2024, just narrowly missing out to Carlos Alcaraz in 2025. The retirement against Griekspoor cost him a 950-point drop in Shanghai, without could have made the path to world number 1 much more achievable in hindsight.
Will this remain Sinner’s Achilles’ heel during the rest of his career? What’s promising is that Sinner has acknowledged these physical setbacks and is working on building on improving his physical conditioning by practicing in Dubai in the off-season where the temperatures are relatively higher compared to Europe. But will a 4-week training block be enough to build long-term resilience to the physical extremes that professional tennis players have to endure all season remains to be seen. Though this might also be genetic, we hope he figures it out, because once he solves this puzzle, he has a real chance of becoming the greatest this game has ever seen.
Thanks for reading! Until next time.