One month after saying the pickleball craze “endangered” tennis, Novak Djokovic will pick up a paddle and play world No. 1 Jannik Sinner in pickleball.

Djokovic, the defending U.S. Open champion and 24-time Grand Slam winner, will face Sinner in The HEAD NYC Mash Up on Thursday ahead of the start of the Open on Monday. Sinner is coming off beating American Frances Tiafoe in straight sets on Monday in the Cincinnati Open final. Two-time major champ Barbora Krejcikova will also participate in the event.

Just last month, Djokovic said that tennis was “endangered” by the growth of pickleball.

“Now we have the padel or pickleball, as you call it in the States, that is growing and emerging,” he said at Wimbledon. “People kind of have fun with it and say, Yeah, but tennis is tennis. Tennis is the king or queen of all the racquet sports, that’s true. But on a club level, tennis is endangered. If we don’t do something about it, as I said, globally or collectively, padel, pickleball in States, they’re going to convert all the tennis clubs into padel and pickleball because it’s just more economical.”

Djokovic and Sinner are just the latest tennis stars to jump on the pickleball bandwagon. John McEnroe, Maria Sharapova, Andre Agassi and Steffi Graf have played in multiple pickleball events on ESPN. Retired American tennis stars Jack Sock and Sam Querrey now play pro pickleball.

According to the Sports & Fitness Industry Association, pickleball participation has increased by 202% in a three-year period.

For McEnroe, tennis will always be the No. 1 racket sport but he hopes that the growing interest in pickleball will help bring more people to racket sports in general.

“When I compare it to tennis, you see athleticism that is incredible on the men’s and women’s side,” McEnroe said, “so I look at it as the king of all racket sports. Everything else is below it, it’s just a question of how much below it?”

He added: “As I reflect, I’m hopeful that this helps both sports potentially because everyone’s like, ‘Is this going to hang on, pickleball? What’s with this thing?’ A lot of people that hadn’t had much time on the court and they aren’t that athletic, they get out [playing pickleball and say], ‘Hey, I can play,’ which is good, get people going.’”

Djokovic, 37, comes to New York after winning his first Olympic gold medal earlier this month over Carlos Alcaraz in Paris.

He is seeking a record 25th Grand Slam title, which would break a tie with Margaret Court for the most ever.

Former British No. 1 Tim Henman thinks winning gold might free Djokovic up to play with “no pressure” in pursuit of No. 25.

“I just don’t think the way he works means he will think he has won the gold medal and that’s it,” Henman told Tennis365. “He still has an enormous passion for the game. He loves what he does and if anything, it might go the other way.

“Winning the Olympics might free him up. He might think he has ticked all the boxes and I am playing with the house’s money now. He might go out and feel no pressure as he looks to win another major at the U.S. Open.

“That might be dangerous for the rest because he will play with freedom and while he is fit and healthy, I definitely think he has more major titles in him.”