You may have seen more of 8th seeded tennis player Rafael Nadal lately, thanks largely to that Tommy Hilfiger ad campaign. Then there’s his day job. The 29-year-old Majorcan athlete is back on the blue courts of the U.S. Open in New York this week. We’re rooting for him in the finals—and we’re envious of his wristwork. For the fifth year running, Nadal is wearing a Richard Mille tourbillon watch made of next generation NTPT carbon and quartz TPT, popular with super-yacht builders for the strength and durability of its materials. And while yes, you may buy the the RM 27-02—with its lightweight design and distinctive orange band—in stores for a cool $775,000, you can also buy Nadal’s very own timepiece. Mille and Nadal are auctioning off the prototype the tennis star is wearing throughout this year’s U.S. Open (worn previously at the French Open and Wimbledon) for the Only Watch auction in Geneva. On November 7th, the Richard Mille creation will be among the other pieces by the likes of Van Cleef & Arpels, Chanel, Breguet, and FP Journe made exclusively for the auction, whose proceeds will benefit research for muscular dystrophy.