How Coco Gauff's Coach Helped Zendaya and “Challengers” Costars 'Transform' Into Tennis Players (Exclusive)

To convincingly play tennis stars in 'Challengers,' Zendaya, Josh O'Connor and Mike Faist "put in the work," says coach Brad Gilbert

<p>Eric Charbonneau/Getty Images for Amazon MGM Studios; MGM /Courtesy of Everett</p> Brad Gilbert; Zendaya in "Challengers"

Eric Charbonneau/Getty Images for Amazon MGM Studios; MGM /Courtesy of Everett

Brad Gilbert; Zendaya in "Challengers"

Some movie magic helped Zendaya and her Challengers costars look like legitimate tennis players — but it would have been impossible without the actors’ hard work on the courts themselves.

“The focus that actors and tennis players have is similar,” says Brad Gilbert, the movie’s tennis consultant. Of Zendaya, Josh O’Connor and Mike Faist, he adds, “They put it in the hard yards.”

The all-around tennis expert — and Olympic bronze medalist — has as a coach led Andre Agassi, Andy Murray and more to victory. Currently coaching a French Open-bound Coco Gauff, Gilbert, 62, says his “first foray” into Hollywood has been a “fun experience.”

Related: Coco Gauff Says She's 'Ecstatic' About Becoming Friends with Fellow Tennis Pro Venus Williams

Collaborating with director Luca Guadagnino, screenwriter Justin Kuritzkes, various producers (including Zendaya, 27, herself), and tennis pro body doubles, Gilbert’s job entailed “making sure everything was authentic as possible,” he says. “All of the players, the opponents, the linesman and ball people.”

Their main focus, of course, were the movie’s three leads, each playing tennis prodigies over the course of years. Faist, 32, “was the only one that had played, in high school,” recalls Gilbert. “Josh literally had never played and Z said she played maybe a couple times as a little kid.”

<p>Michele Eve Sandberg/Icon Sportswire via Getty</p> Brad Gilbert and Coco Gauff on March 19

Michele Eve Sandberg/Icon Sportswire via Getty

Brad Gilbert and Coco Gauff on March 19

Being their tennis consultant meant beginning with three months of hard training in Boston, Massachusetts: “A short period of time to transform them,” as Gilbert points out, but something “they do a lot as actors.” The stars would leave daily at 6:00 AM and start a two-hour practice at 7:00 AM. “Then all afternoon they had to work on their acting,” he adds. “So, we had long days to get ready just to start filming.”

Related: Zendaya Reveals What Serena Williams Told Her After Watching Challengers

Furthermore, Guadagnino and the Challengers team had specifications on Zendaya, O’Connor and Faist’s physicalities. Recalls Gilbert: “Mike had to eat like 10,000 calories a day because Luca wanted his character to be thicker. He was coming from West Side [Story] and he was too thin. Josh was a little bit thicker, and they wanted him to be thinner. They wanted Z to be a little more cut. So, they all had different things they had to work on.”

Then there was research. “My wife [Kim] sent them all a ton of videos to help them understand” tennis moves and famous players, says Gilbert. Faist’s character Art was designed to be “this classic player with a one-handed backhand, a little bit patterned after a Pete Sampras.” Zendaya’s character Tashi, meanwhile, was a “killer” on the court, whereas O’Connor’s Patrick “was more of this free wheeler.”

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Also, every play in Challengers’ many tennis matches had to be staged. “In tennis, nothing is choreographed. It's in real time,” Gilbert explains. But in moviemaking, “we didn't just all of a sudden just freewheel it. When we do the six-ball rally and it ends this way, we have to [practice] it 50 times… I had an actor on each different court practicing their routine, what they needed to do, so learning [their] part for each one of those points.”

Guadagnino would then observe Zendaya, O’Connor or Faist executing each point and provide feedback depending on his desired camera work, pacing and more. “I would build it and then Luca would come and watch it and say, ‘I want it to be a little faster, or a little shorter’ … Then we would tinker with it and redo it.”

<p>Stewart Cook/Getty Images for Amazon MGM Studios</p> Brad Gilbert and Zendaya at the "Challengers" premiere on April 16

Stewart Cook/Getty Images for Amazon MGM Studios

Brad Gilbert and Zendaya at the "Challengers" premiere on April 16

So how does the actors’ training compare with the final product? Fresh off seeing Challengers for himself, Gilbert reports, “I was really happy. All of them put in the work [and] did a great job.”

Related: Coco Gauff Says She Likes Keeping 'Some Parts' of Her Personal Life to Herself (Exclusive)

Plus, he quips, “They were fun to work with” and shared plenty of “camaraderie and chemistry.” Gilbert’s favorite memory involves O’Connor having to hit a tweener — a tricky between-the-legs shot — and nailing it during a practice. 

The only issue? No cameras were rolling. “We practiced this so freaking much, and that was the toughest shot for Josh to be able to do,” Gilbert remembers. The Crown star "hit an unbelievable tweener, a one-in-a-million shot. I could not believe we didn't have it on film.”

Zendaya, meanwhile, “has a lot of DNA of a tennis player,” says Gilbert (who notes that his fellow Oakland, California native was born in the same hospital as him). The Dune star is “really dedicated to what she's doing and doesn't take anything for granted. She's a pleasure to be around… because of the focus, the grit, the determination it takes to transform yourself to become this character.”

Challengers is in theaters now. 

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