Former World No.1 Refuses to Buy Into Jannik Sinner’s Heat Rule Claims: “I Don’t Believe It”

If anyone has played tennis in the Australian summer, they have a tiny fraction of an idea of what Jannik Sinner went through this weekend. But the physical toll on the defending champion isn’t the only thing heating up Melbourne. A fresh controversy has broken out off the court, with doubles specialist Jamie Murray throwing some serious shade at the official narrative coming out of the Italian’s camp.

The Australian Open is famous for two things: incredible tennis and absolutely brutal weather. When those two collide, things get messy. And when scheduling politics gets into the mix, there is drama that has everyone from fans to former champions scratching their heads.

I don’t believe it. There’s no way he went through what he went through in his last match and then they didn’t want him to play as late as possible. I don’t believe it personally, but I could be wrong. I’m not saying he’s wrong. He’s absolutely in his rights to ask to play late in the day, but I don’t believe he went through what he went through and did nothing about it.

Jamie Murray said on TNT Sports

After the match, the conversation shifted from Sinner’s survival to why he was playing in those conditions in the first place.

Usually, top-tier stars like Sinner get the prime-time slots—the night sessions where the air is cooler, the lights are on, and the risk of heatstroke is practically zero. Yet, the Italian was out there baking in the day session.

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Sinner’s coach, Darren Cahill, came out with a surprising statement. He insisted that the team “did not request a night session” and that they had “no problem sticking to the schedule” given to them. Murray wasn’t having any of it.

The Meltdown in Melbourne

Jannik Sinner, the World No.2, was in the middle of a third-round clash against American Eliot Spizzirri. It wasn’t supposed to be a survival mission, but the Melbourne sun had other plans.

Sinner wasn’t just tired; he was crumbling. We’re talking full-body cramps—the kind where your hands lock up, and your legs refuse to listen to your brain. It looked like the defending champ was about to make a shock exit, not because of his opponent’s skill, but because his body was shutting down.

Then, arguably the biggest stroke of luck of the tournament happened. The “Heat Rule” kicked in. This rule, designed to protect player welfare when the wet bulb globe temperature hits a certain threshold, mandates a 10-minute break.

For Sinner, it was a lifeline. He managed to recover, regroup, and eventually win. But the timing of that break raised eyebrows. Many legends, including John McEnroe, focused on the timing of the delay.

What comes next for Jannik Sinner?

Despite the drama, Jannik Sinner is through. He even managed to beat his compatriot Luciano Darderi in straight sets in the following round, extending his dominance over fellow Italians. He survived the heat and the cramps.

But the questions Murray raised won’t go away immediately. As the tournament deepens and the stakes rise, scheduling decisions will be under a microscope. Will Sinner get the night sessions now? Almost certainly.

One thing is for sure that if he gets to the semifinals, he is certain to have a night session semifinal. According to the previous schedule, men’s semifinals used to happen on Thursday and Friday. Now, both the semifinals take place on Friday.

The top half of the draw will have their semifinal in the day session. The bottom half of the draw will have their semifinal in the night session. Sinner played the day session semifinal in 2024, and the night session semifinal in 2025.

Also Read: (Video) Jannik Sinner Couldn’t Stop Smiling Seeing his Doppleganger at the Australian Open