In two of the biggest sports moments of the weekend — a much-hyped NFL season opener and the U.S. Open men’s singles final — Richard Mille nearly stole the show.

One of the luxurious watches produced by the Swiss brand, oddly, turned up on the left wrist of Odell Beckham Jr. on Sunday as the wide receiver made his debut with the Cleveland Browns. That day, another Richard Mille timepiece was front and center on the right wrist of Rafael Nadal, as it so often is, as he was winning his 19th Grand Slam tournament. Together, the two watches were worth nearly $1 million.

Beckham chose to wear an orange RM 11-03 Automatic Flyback Chronograph McLaren that cost him $189,500 at a Richard Mille boutique, a company representative wrote in an email, and it’s a decision that became controversial. After raising eyebrows by wearing the watch during Cleveland’s Week 1 loss to the Tennessee Titans, Beckham plans to wear the watch Monday night when the Browns play the Jets on national television.

“It shouldn’t be an issue,” Beckham said Tuesday, adding that he’ll wear it “the same way I wear it every day, at practice. I go here, I go there. I’ve been wearing it. Take a shower with it on. It’s just on me.”

The NFL has rules, though, about what players can wear on the field and it prohibits players from wearing “metal or other hard objects that project from a player’s person or uniform.” On Monday, the Associated Press reported that the league planned to speak with Beckham about the matter.

“I’m here to play football,’’ Beckham said. “I would love for them to talk about football and what I do on the field, if I messed up on the field or if I didn’t do well on the field, talk about my performance. Don’t talk about any extracurricular, that’s just it. If anybody else would’ve worn the watch, or if it was a $20 watch, it wouldn’t have been no problem.’’

Beckham pointed out that “watch is plastic” and added that “people have knee braces on that are hard and made of metal and you don’t see them taping it up, no jewelry on, so I’m good.”

Ah, but it wasn’t “a $20 watch.” It was one of only 500 that were made of that particular model, and the receiver paid for it with his own money, which means the loss would be his. Unlike Nadal and other sports stars, Beckham “is not a brand partner and it is his decision to wear his watch on the field,” a company spokeswoman wrote.

Although Beckham is on his own, the company has always cultivated relationships with athletes. “Since the brand began, Mr. Mille only forms partnerships with athletes who commit to wearing a Richard Mille watch while they perform their sport,” Laura Hughes, director of communications at Richard Mille, Americas, wrote in a statement. “They provide the ultimate proving ground for the highly complicated timepieces that are created to be ultra comfortable and precise timekeepers in extremely challenging physical conditions.”

Individual sports are often more forgiving than the NFL when it comes to branded accessories. For those competitors, wearing a watch while competing is a smart business arrangement, another advertising opportunity for sponsors. Rolex and Omega, for instance, have long partnered with athletes in individual sports, and Nadal has been a brand ambassador for Richard Mille for years. That explains why he wore one of the company’s watches while beating Daniil Medvedev in the epic five-set final Sunday. (Medvedev has his own side gig with luxury watchmaker Bovet 1822.)

For Nadal, the RM 27-03 Tourbillon Rafael Nadal limited-edition watch (which retails for $769,000) is something of a good-luck charm, and his model is a nod to his native Spain, according to the Richard Mille website. “The striking red and yellow hues of its Quartz TPT case pay homage to Rafa’s native Spain, while the upper skeletonized bridge evokes the forward-facing head of a bull,” the site says, in subdued prose. “A symbol of Spain, this animal is also Nadal’s chosen emblem.”

The RM27-03 was designed to absorb the force of Nadal’s swing, Forbes reported, and, in promotional material, Nadal also said the timepiece feels right.

“Richard came to my house and showed me a model saying: ‘This is the watch that we made for you,’ ” Nadal said in a blurb on the company’s website. “The watch was in platinum so [it was] very heavy, I was very confused and didn’t realize that he was joking. As soon as I tried the real watch on, I loved it. We were on the same wavelength. The watch is now like a second skin for me."

It’s a second skin that isn’t for everyone, though. The company, based in Les Breuleux, Switzerland, was founded by Dominique Guenat and Richard Mille in 2001 and produces opulent timepieces that cost — well, if you have to ask, you can’t afford it.

Richard Mille has company in the high-end watch sponsorship realm. Roger Federer often wears a Rolex Oyster Perpetual Datejust, among other models. Novak Djokovic, a brand ambassador for Seiko, wears a $2,000 Seiko Astron Novak Djokovic Limited Edition GPS solar-powered watch that bears his signature on the back. Serena Williams wore an Audemars Piguet watch during the U.S. Open women’s final Saturday and Naomi Osaka sported a Citizen Eco-Drive Bluetooth watch during the Open.

Richard Mille also works with polo players, Formula 1 drivers, skiers, track and field athletes and golf star Bubba Watson.

“Richard Mille has had a genuine relationship with professional athletes for many years,” Hughes told Complex, “and it only gets deeper.”

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