Top-ranked Jannik Sinner is feeling optimistic about his Wimbledon title defense after sweating through an exhibition match in a heat wave on Wednesday (June 24, 2026) and confirming he underwent testing following his physical meltdown at the French Open.

The Italian star hasn't entered any tour-level events in the buildup to the grass-court Grand Slam, which starts Monday (June 29, 2026), so his 6-3, 6-3 victory over Cam Norrie in sweltering west London will have to suffice.

“It was very warm, but physically I felt good,” Sinner told reporters.

The appearance at the Giorgio Armani Tennis Classic came just under a month after the Italian star struggled with dizziness in a stunning second-round loss at the French Open.

“We did some testing. We tried to understand what happened,” he said. “We came to a conclusion which is very good.” Wednesday's match went ahead with southern England under a “ red warning ” for extreme heat issued by Britain's national weather service.

“As Cam said, a very hot day,” Sinner said in an on-court interview. “Exhibition matches, they are good because we try out a couple of things and hopefully be as good as we can then for the next week." The interviewer asked him what he was trying out. “I don't know," a smiling Sinner responded.

Earlier on Wednesday at the All England Club, Sinner wore a cooling vest at practice. During the match against Norrie, he didn't use ice packs like in the past.

The early afternoon temperature in Fulham, where the grass-court event was held, was 33 C (91.4 F) with a slight breeze.

The temperature at Wimbledon on Monday is expected to be a much more manageable 24 C (75 F).

In Paris, he was ahead by two sets and 5-1 in the third before losing to Juan Manuel Cerundolo 3-6, 2-6, 7-5, 6-1, 6-1. The temperature on Court Philippe-Chatrier rose to 32 C (90 F) during the match, and Sinner was clearly having a tough time cooling himself down as he reached for multiple ice bags.

Sinner, who has a history of problems with heat and cramps, didn't blame the heat entirely after the loss. “I think many things together caused this problem. I just need my time now to process what went wrong here,” he said at the time.

At the grass-court major a year ago, Sinner beat Carlos Alcaraz 4-6, 6-4, 6-4, 6-4 in the final for his first Wimbledon title. Alcaraz will miss this year's tournament because of a wrist injury.

The U.K.'s weather service said the region could see "a two to three-day period where maximum temperatures in the shade exceed 37 Celsius, perhaps rising to 38 to 40 Celsius in some places. The heat will be accompanied by high humidity, exacerbating the potential for discomfort and health impacts, with very warm and humid night times also reducing the ability for people to recover overnight.”

Heat impacts Wimbledon qualifying tournament

Because of the heat warnings, the ball boys and ball girls for Wednesday's matches at Wimbledon's qualifying tournament were kept home. Their duties were handled by “our Court Services team — who are all adults,” the All England Club said.

Also Wednesday, there was a temporary loss of power to part of the Roehampton qualifying venue “which meant that the electronic line calling system could not function,” the club added. Heat will be looked at as a possible cause for the outage.