Kevin Connolly Humbled by the Michael Phelps Phenomenon

Entourage star says shooting with the swimming champ was "like being in New York City with one of the Beatles"

The Phelpsian frenzy shows no sign of slowing down.

When Michael Phelps shot an impromptu cameo for the new season of Entourage this week, the HBO comedy's fab four got a taste of what hanging out with the original Fab Four might have been like.

"It was like being in New York City with one of the Beatles," Kevin Connolly told E! News Friday about shooting a scene with the 14-time Olympic gold medalist, who's been the toast of seemingly every town since returning to the U.S. from Beijing.

“People were stopping in the streets and climbing up things to see him. They were going nuts. He’s like a superstar."

"It was fun," albeit "pretty humbling," added the actor, whose hit HBO show has its fifth-season premiere Sept. 7.

The Entourage spot, of course, was only the tip of the iceberg for Phelps, who has also lined up a Sept. 13 hosting gig on Saturday Night Live, presenting duty at the MTV Video Music Awards Sept. 7 and, now, the season premiere of The Oprah Winfrey Show.

He'll appear with about 175 other members of the U.S. Olympic team, including NBA star Kobe Bryant, gymnast Nastia Liukin, beach volleyball champs Misty May-Treanor and Kerri Walsh and swimmer Dara Torres, for a "Welcome Home Team USA" celebration.

The episode is set to tape Wednesday at Millennium Park in Chicago, which is hoping to be the home of the 2016 Summer Olympics, and will air Sept. 8.

So, the America's Homecoming Parade that Disney World held for the star swimmer today in Orlando was really more like the unofficial launch party for Michael Phelps Month, aka September.

And yet, through it all, the 23-year-old Baltimore native still seems to be most comfortable in his old splashing grounds of Any Pool U.S.A.

After a whirlwind Thursday that included the Entourage shoot, an appearance on Good Morning America and a bunch of other interviews, Phelps looked most at ease when he slipped into the pool at the McBurney YMCA in Manhattan to present a $20,000 check on behalf of megasponsor Visa to the Partnership for Play Every Day, which promotes the importance of regular recreation time for kids.

“For America’s kids, the time to play and swim is today,” Phelps said. “We need everyone’s help in providing all kids with safe and well-equipped spaces where they can exercise, have fun and maybe even begin to pursue their own Olympic dreams.”

"He was a trooper," an event rep told E! News. "From the look on his face, being in that pool was the highlight of his day. All the stress just melted away."

—Additional reporting by Matt Donnelly and Whitney English