Blink and you'd miss it!
Olympic hero Michael Phelps filmed a cameo for HBO's "Entourage" in August, and it finally aired on Sunday night's season finale.
Shot on the streets of New York City, the scene features Eric (Kevin Connolly) on the phone having an argument with Ari Gold (Jeremy Piven). Eric bumps into someone, who then turns around and is revealed as the swimmer.
Phelps even gets in a line: "Yo! Watch out man. What's up?"
(WARNING: PIVEN'S CHARACTER SAYS TWO OBSCENITIES IN THE SCENE)
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