Roach calls the duo’s thematic approach to red carpets “method dressing” – a nod to the acting technique – and it’s a hallmark of the pair’s collaboration.

Throughout the film’s international premieres and the cast’s promotional appearances, Zendaya has served up looks with tennis whites, collars and pleats, sportswear fabrics like mesh and even actual tennis balls.

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These sporty yet chic silhouettes dominated her promotional appearances and photo calls – including an April 14 stop in Milan, where she sported a 1992 Ralph Lauren dress that Cindy Crawford had originally modelled.

Some of her other get-ups were more on the nose, featuring actual tennis balls. During a visit in Rome, Zendaya wore a glitzy custom Loewe dress with a pleated skirt – a prime example of the elevated tenniscore looks she and Roach have crafted. The main attraction of the ensemble, though, were stilettos with tennis balls at the bottom of the heels.

Another tennis ball popped up as the centrepiece of a custom bright green gown at the after-party for the Los Angeles premiere. The bold look came hours after Zendaya stepped onto the red carpet in a black and pink corset ball gown, prompting fans to think it marked the end of her method dressing on the press tour.

Some of Zendaya’s looks were less obvious than others, like those that featured touches of tennis ball chartreuse or tennis whites. Roach said one all-white look paid homage to Althea Gibson, one of the first Black athletes to play international tennis and the first Black player to win a grand slam event title.

“You want to get it right and you want to make them proud,” Roach said. “And you can’t really get a better compliment than from someone like Venus Williams.”

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Many Challengers ensembles also incorporated silhouettes or styles from the 1960s and 70s, likely in acknowledgement of the period when women’s tennis gained traction and attention. In one checkered mod look from Louis Vuitton, the star nailed the tennis inspiration without going over the top. She similarly rocked a pink 60s-inspired dress with a tennis-like collar and modern cut-outs on her torso.

The splashiest, and most talked-about, look from her tour was Zendaya’s custom Loewe gown that featured the silhouette of a tennis player preparing to serve a ball. She wore the shimmering green dress with matching heels to the Sydney premiere in March, which kicked off the conversation about her long history of method dressing.

“With Law and I, we always find inspiration from films that I’m doing,” Zendaya said in a recent interview with Vogue. “A butterfly isn’t the theme per se, but it is this idea of being costumey. You’re the greatest showman, and so everything is drama, and that’s what this dress was to me.”

Zendaya and Roach are method-dressing pioneers, but Roach acknowledges that others used the technique before them.

“We can take some responsibility for bringing this trend to the forefront, but we don’t think that we’re the first people to ever do it,” Roach said. “Geena Davis did it in 1992 at the premiere of A League of Their Own – she had this little white dress with baseball stitching. Glenn Close did it when she played Cruella de Vil. We’re not saying we invented it, but we have been very much purveyors of it for these last films that [Zendaya has] been in.”

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Other stars have donned looks inspired by their projects in the past – most recently Jenna Ortega for Wednesday, Halle Bailey for The Little Mermaid, Dakota Johnson and Sydney Sweeney for Madame Web, and Zoë Kravitz for The Batman. Angelina Jolie, Emma Watson and Keira Knightley also nailed the trend years ago.

Method dressing is likely here to stay, and Roach is hoping it will spill over from red carpets to cinemas. Roach predicts tenniscore looks will take over this summer and has been reposting on social media Challengers theatergoers in their tennis skirts and chic white looks.

“It’s just fun,” he said. “There’s a lot of things going on in the world and I’m not naive to think that fashion or movies can change that. But I think sometimes just adding something that can bring joy into people’s lives is really the point.”