Olympic superstar Michael Phelps, who’s already set to host Saturday Night Live, will make a cameo on the HBO comedy Entourage later this year. Phelps scored the gig after literally stumbling upon the show’s set while it was recently shooting in Manhattan. After learning how Phelps was a big fan, series producer Doug Ellin immediately wrote the gold medalist into the episode. He’ll interact with Kevin Connolly‘s Eric Murphy in an episode scheduled to air later this year. Entourage begins its fifth season Sept. 7.