PARIS (AP) — Tennis players at the French Open say they haven't experienced conditions this hot at Roland Garros since the Paris Olympics.

And the 2024 Olympics were held in July and August.

Temperatures for the opening two days of the clay-court Grand Slam have soared to 33 degrees C (91 F) — far beyond normal for late May in the French capital. And it's forecast to stay that way for the entire first week.

Besides making it uncomfortable for fans and players alike, the sultry conditions have also created faster conditions on court — changing the pace of the game.

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"It is much different. Maybe it was that hot in the Olympics but the balls were different, so I wouldn't treat it as the same tournament," four-time French Open champion Iga Swiatek said after routing Emerson Jones 6-1, 6-2 in the first round on Monday.

Players have been putting bags of ice around their necks on changeovers to stay cool, while fans are refreshing themselves under sprinklers.

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When workers water the clay courts between sets, they have taken to directing their hoses at spectators begging to be doused, too.

"I don't remember the last time it was so hot at Roland Garros," Russian-born Australian player Daria Kasatkina said after beating Zeynep Sonmez 6-4, 6-4. "Maybe one day. But we're going to have it for the whole week."

Kasatkina said the energy-sapping temperatures made for more up-and-down matches.

"You can suddenly just get out of the bench and feel that your focus dropped," she said. "So this is a battle which you have to also win. … Whoever adapts better to today's conditions gets it."

A retirement and medical timeout

Canadian player Gabriel Diallo said the heat was the main reason why he retired midway through his match against James Duckworth on Sunday.

Both Andrey Rublev and opponent Ignacio Buse called for the trainer on separate occasions during the second set of their match on Monday.

Buse took a medical timeout and had salts and minerals added to his water bottle as a stethoscope was placed on his chest. Rublev received treatment a few games later.

Heat protocol

The French Open is usually cool compared to the heat at the Australian Open and U.S. Open.

But like in Australia and New York, the French Open has adopted an extreme weather policy.

If the Wet Bulb Globe Temperature (WBGT) — which takes into account temperature, humidity, sun, wind and other factors — reaches 30.1 degrees C (86 F) or higher, 10-minute cooling breaks can be installed between the second and third sets for women's matches and between the third and fourth sets for men's matches.

If the WBGT hits 32.2 C (90 F), play is suspended. It would require an air temperature of about 38 C (100 F) for play to be suspended.

Fast-court players like the heat

Some players were embracing the hotter air.

"I've always preferred hot and lively conditions to chilly on a clay court, because I feel like I can bring a little bit more of my all-court tennis on this type of surface," Australian player Alex de Minaur said after beating Toby Samuel 6-4, 6-4, 6-2.

"It's easier to be a little bit more aggressive. The ball is jumping. I don't necessarily have to use as much spin or heaviness, and I can let the conditions do the job for me. And it's quite physical. I don't mind the heat," De Minaur added.

Same goes for American player Alex Michelsen, who eliminated Alexander Shevchenko in straight sets.

"It's definitely good for us Americans," Michelsen said. "Generally we're big serve, big forehand, big ground game and like to play offense. When it's super hot, the ball is moving through the air very fast. … I was so happy when I saw the forecast."