By now, the tennis community has learned that Jannik Sinner’s toughest rival right now might be the heat rather than anyone across the net. Time and again, the Italian has succumbed to harsh weather conditions, a concern that has become increasingly evident over the past year.
As he begins preparations for his Wimbledon title defense in the midst of London’s sweltering heatwave, Sinner has opened up about the collapse he suffered at the French Open last month.
Jannik Sinner Believes ‘Every Tournament Is Getting Warmer and Warmer’
Sinner skipped the tune-up events on grass ahead of Wimbledon and participated in the Giorgio Armani Tennis Classic exhibition event at the Hurlingham Club instead. He played his first match on the surface on June 24, winning with a 6-3, 6-3 score against Cameron Norrie.
With the temperatures hovering around 36 degrees Celsius (96.8 degrees Fahrenheit), Sinner conveyed that training in the heat would be a deliberate choice moving forward, aimed at better conditioning his body to cope with extreme temperatures.
“Today, was no wind at all, so it was maybe even warmer, but it’s good. That’s exactly what I need, a good preparation before starting the tournament,” he said at the Hurlingham Club.
“In future, we will always try to practice where the warmer conditions could be, because I feel like every tournament is getting warmer and warmer every year, so it’s going to be important, but we did a lot of work, and today was a good preparation,” he added.
Sinner’s inability to withstand heat has become one of the most widely discussed issues in tennis. Yet his struggles in extreme conditions remain puzzling. He has won the Australian Open twice during Melbourne’s scorching summers, captured Wimbledon amid the 2025 heatwave, and triumphed at Indian Wells this year in similarly hot conditions.
On the other hand, the heat-related incidents have piled up. At the 2025 Cincinnati Open, Sinner retired from the daytime final while trailing 0-5 against Carlos Alcaraz, with illness and the intense heat contributing to his decision.
In Shanghai, Sinner’s physical condition deteriorated in the third set of his match against Tallon Griekspoor, as oppressive heat and humidity appeared to take a toll on his body. In Melbourne this year, the World No. 1 almost retired from his third-round match against Eliot Spizzirri before the extreme heat rule was implemented.
More recently, Jannik Sinner crashed out of the French Open in the most shocking fashion after leading 6-3, 6-2, 5-1 against Juan Manuel Cerundolo.
Sinner, who won five Masters 1000 events in a row between March and May, took an extended break after his French Open exit. He resumed training at the Monte-Carlo Country Club after a vacation with his family. Here, he was spotted using what appeared to be a continuous glucose monitor (CGM). He also underwent blood tests in Milan and reportedly visited J Medical in Turin to better understand his complications.
“We did some testing; we tried to understand what happened. We came to a conclusion which is very good. So we worked very much; we changed the work a little bit as well, trying to see how my body reacts in different conditions,” he said about the collapse in Paris after his exhibition match on Wednesday.
MORE: Jannik Sinner Opts for Cooling Vests, Wimbledon Suspends Qualifying Matches As ELC Fails in Heatwave
Over the past couple of years, Sinner has shifted his off-season base from Monaco to Dubai in a bid to better prepare for the Australian Open conditions. Yet the four-time Grand Slam champion still seems to have ground to cover in understanding the heat — arguably his biggest rival right now.
