'Entourage' Stars: Michael Phelps Stopped Traffic

Access Hollywood

NEW YORK, New York -- Olympic champ Michael Phelps has made one TV appearance after another since earning eight gold medals at the 2008 Beijing Olympics, but his favorite cameo thus far? - HBO's "Entourage."

The swimmer filmed a cameo for the HBO show's fifth season last week in New York after appearing on "Good Morning America."

"That was an amazing sort of serendipity moment when Michael Phelps just happened to be in the neighborhood and somebody asked him, 'Hey, want to be in 'Entourage?' and he said, 'Of course, it's my favorite show,'" series star Adrien Grenier told Access Hollywood at the season five premiere in New York on Wednesday night. "And they just wrote him into that scene."

Olympians On Oprah: Michael Phelps - Play it Now

According to co-star Kevin Connolly, the Olympian was golden in front of the camera.

"He did a good job," Kevin said. "Considering we plucked him off the street and stuck him there and [said] 'Do this,' in two seconds. He didn't have to much time to think about it."

Neither did show creator Doug Ellin, who had to write Phelps' part almost as fast as the swimmer's record-breaking times.

All Access: Michael Phelps - HBO - 2008 Beijing Olympics - TV

"Well, it started a couple weeks earlier," Doug admitted. "I get an e-mail that Michael is a fan of the show and would love to do it. And this was when he had six medals, so I'm like, 'It's weird, why is he thinking about this?' which felt really good. And I sent it to everybody I knew. And all the actors were like, 'We got to get him,' and I wrote back, 'Anything that he wants to do, I will find something for him.'"

"Two weeks later, we were shooting in New York and I'm asleep still because it was 7 o'clock in the morning [and] I get a call," he continued. "Michael Phelps' people just walked by and he would love to do one, can you come over or something? I said, I would be there in five minutes."

Phelps, who played himself, was show stopping.

"The entire street stopped," Doug said. "I'm not exaggerating. Like buses stopped, everything, and we did three takes and at the end of that, he had to go, because New York had stopped moving."

Doug was less revealing about the details of Phelps' performance, but he did call it "cool."

"He plays himself, it's a very small thing, but it's very subtle and cool and very New York," he said. "And basically what happens, you are walking down the street and it's like, 'Is that Michael Phelps?' That's how it kind of is."

Even Jeremy Piven, who plays angry super-agent Ari Gold, had good things to say about the Olympian.

"Well, Michael Phelps is a fairly driven gentlemen," Jeremy deadpanned to Access. "He's accomplished a few things in his life. I'm actually completely inspired by that guy, I really am and we all are and the world is and so, what a blessing that he watches our show."

And the cameo might not be the end of Phelps' entry into "Entourage."

"He will come back," Jeremy said. "We just got to figure out when. He's on a victory lap that may never end."

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