(CNN) New balls please!
It's proving to be a French Open like no other. Played in autumn rather than summer, some players have been complaining about the cold weather and the tournament's switch from Babolat to Wilson balls.
"The ball is completely different," defending men's champion Rafael Nadal told reporters last week. "The ball is super slow and heavy. (There are) very cold, slow conditions.
"I think (it's) not a good ball to play on clay, honestly. That is my personal opinion. It's not the right ball to play on clay courts."
Cooler temperatures mean Nadal's heavily spun forehand won't have as great of an effect on the clay of Roland-Garros.
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Briton Dan Evans, who lost to Kei Nishikori in five sets in the first round on Sunday, was in agreement with the 12-time French Open champion, saying some of the balls you "wouldn't give to a dog to chew."
"I think the balls are the biggest thing," he said of the challenging conditions, while also acknowledging the cold.
"Maybe they got it a little wrong with the balls. It's tough to get that ball to go anywhere. It's in what month, September, October? That ball is a bit too heavy, I think."
US Open champion Dominic Thiem also lamented the change, saying the Babolat previously used at Roland-Garros was "perfect" for topspin and his "favorite ball."
But not all players are against the switch, with world No. 5 Daniil Medvedev saying the new balls suit his game.
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This year's French Open has been moved from its usual May start date amid the coronavirus pandemic, meaning temperatures are cooler than normal.
Players were wrapped up in multiple layers as the tournament got underway on Sunday.
Former world No. 1 Victoria Azarenka was among those to suffer in the conditions, complaining to a match supervisor that she was "frozen" during a lull in her first round match.
It was announced in November 2019 that the French Tennis Federation had signed a five-year partnership with Wilson, which made the company the official ball of the French Open.
The announcement said the ball had been "designed specifically for the famous clay courts of Roland-Garros" and Hans-Martin Reh, general manager at Wilson Racquet Sports, said the company is committed to "creating the best clay-court experience for players."
According to The New York Times, French Open tournament director Guy Forget said the Wilson ball had passed performance tests before being introduced and that no ball could function effectively given the current weather conditions in Paris.
Wilson did not immediately respond to CNN's request for comment.