Tennis legend Roger Federer is used to partnering with some of the biggest brands in sports. This year, he ranked highest among fellow athletes in endorsement revenue, according to Forbes, earning a total of $86 million from companies like Credit Suisse, Mercedes-Benz, Rolex and Japanese apparel brand Uniqlo.
But a recent deal the 20-time Grand Slam tennis champ made speaks to an off-the-court passion: sneakers. He owns over 250 pairs.
During an event for his new deal with Swiss shoemaker On, Federer talked about how important it is for young people to have an obsession.
"You don't have to have 250 pairs of sneakers," Federer tells CNBC Make It. "I can tell you that."
"But I think obsession can definitely lead to some good things sometimes because you really follow something that you're really passionate about," he says. "And when you do that, passion doesn't feel like work."
Federer's first passion may have been tennis, but his initial Nike deal as a teenager sparked his interest in sneaker culture, including both tennis shoes and basketball shoes, he told Complex Networks in a 2014 interview.
Today, that obsession has parlayed into his new business venture as an investor, advisor and product designer for On. "I don't think working on On has felt like work or like a business," Federer says. "It's been more [of a] fun process."
Though Federer is quick to tout the passion that comes from having an obsession, he also hints at its downside. "Of course, it can become excessive and then it becomes dangerous," Federer says. "Then you need to take a break. You need to take a step back with everything you do, because if you do it too much you sometimes lose the fire."
The tennis star knows this firsthand. Federer not only prioritizes his rest — he sleeps an average of 12 hours per day — he also enjoys his vacations.
"I know, in my mind, vacations are what keep me sane through the entire crazy process that I go through because I am obsessed about tennis and about life," he says.
As for his passion for sneakers, "I think it can work both ways," Federer says. "But I'd say, like [in] this case, a sneaker obsession is an okay thing."
Editor's note: This story has been revised and updated.
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