Frances Tiafoe sweats a lot. The 24-year-old American tennis player had a breakout performance at this year’s U.S. Open, beating Rafael Nadal in the round of 16 and making it all the way to the semifinals. During each match, he repeatedly changed his shirt.

After he lost to Carlos Alcaraz (who would go on to win the tournament) in a tense match on Friday, Mr. Tiafoe gathered the discarded pile of his soaked shirts into a ball, stuffed them into his tennis bag and walked off the court with great disappointment — he and his shirts having more than captured the attention of tennis fans.

Maroon, with the palest of pink short sleeves and a horizontal neckline bisected by neon orange zipper, looking a little like an apron worn over a blouse, the Nike shirts became part of the spectacle. Mr. Tiafoe was not the only player wearing this peculiar shirt. Two other U.S. Open standouts, Karen Khachanov and Jannik Sinner, did as well. Mr. Khachanov wore it in the same colors as Mr. Tiafoe, while Mr. Sinner wore the shirts in white and navy.

The design was polarizing for many spectators.

“Nike did their peeps dirty on these shirts,” one Redditor wrote. “Who at Nike thought ‘grocery store bagger’ would be a good look for a tennis shirt?” a Twitter feed mused. During the match in which Mr. Khachanov was eliminated, another Twitter user joked that his opponent, Casper Ruud, was going to win “because he doesn’t have to wear the cursed Nike US Open tennis shirt with the zipper.”

Although many fans didn’t seem too keen on the shirt, dressing up players in unorthodox attire is quintessential Nike. For the 1988 U.S. Open, the sportswear company outfitted Andre Agassi in a pair of jean shorts. “Dressing like me in 1988 means wearing denim shorts,” Mr. Agassi wrote in his autobiography, “Open.” “Sportswriters murder me for it.” The iconoclastic jorts were not his idea, he said.

For the 2005 French Open, the Nike-sponsored Mr. Nadal made headlines for wearing white clam diggers — bottoms that were much longer than traditional tennis shorts. “Nike decided I should wear them,” Mr. Nadal said at the time. “But I like them.”

Nike’s “corporate ethos for the last couple decades, not just in tennis, but throughout sports apparel, is to challenge convention, to be quote-unquote outrageous, and to get people to pay attention, even if it’s sometimes negative,” said Paul Lukas, who has been writing the column Uni Watch, about sports uniforms and athletic aesthetics, since 1999. “The U.S. Open in recent years has especially been a showcase for that, because it’s the first major championship that follows Wimbledon, which is the most staid and conservative of all the tennis championships, since everybody has to wear white, and that conforms more to tennis’s country club heritage.”

Mr. Lukas said that as tennis has become an increasingly racially diverse sport, “the designs we see people wearing reflects that as much as it reflects changing notions of what is and isn’t acceptable for people to wear on the court.”

Nike dominates American professional sports attire. The company makes the uniforms for the N.B.A., the N.F.L. and Major League Baseball. While tennis players don’t wear uniforms, there are rules for what they are allowed to wear. (The sport has several governing bodies, and each Grand Slam is coordinated by a different organization with different dress codes.)

Nike’s ideology when it comes to outfitting athletes, Mr. Lukas said, is moving “away from the idea of an athlete wearing a uniform and more toward the idea of a superhero wearing a costume.”

After Serena Williams wore a Nike catsuit at the 2018 French Open, deviating from the standard skirt, Bernard Giudicelli, the French Tennis Federation president, told Tennis Magazine that it “went too far” and “it will no longer be accepted. You have to respect the game and the place.”

In response, Nike created an advertisement with an image of Ms. Williams. It read: “You can take the superhero out of her costume, but you can never take away her superpowers.” (Nike declined to comment for this article.)

Since Nike dresses its athletes like superheroes, the display at this year’s U.S. Open would suggest that in 2022, the Übermensch is not afraid to sport a pink blouse.