Jason Segel Starstruck By Brad Pitt and Angelina Jolie

 Jason Merritt/Getty Images; Steve Granitz/WireImage.com

Jason Segel has starred in a series of box office hits — Forgetting Sarah Marshall, Bad Teacher and Knocked Up — but the 31-year-old actor still feels out of place at Hollywood events.

"One time I was on a red carpet and Brad Pitt and Angelina Jolie came up to me and they said, 'We just watched Sarah Marshall. We just wanted to say hi. Great job!'" Segel recalled during a Tuesday appearance on The Tonight Show with Jay Leno. "And my response was, 'Oh, my God! It's you!"

Segel was similarly starstruck when he was recently introduced to Lady Gaga, former President Bill Clinton and U2's lead singer, Bono.

"I've never felt more out of place, but I thought, 'It's worth it because I'll remember this moment for the rest of my life.' Then President Clinton came up to talk to me, and at that point, from then on, I have no recollection at all," Segel laughed. "I know he was charming. I don't think I said anything at all. I'm bad with this stuff."

"The same thing happened backstage with Lyle Lovett," The Muppets star told Leno. "He came into my room to say, 'Hey, I'm a big fan,' and I think I just stared at him."

Leno, 61, then teased Segel for not appearing nervous around him. "Yet you have no trouble talking with me," Leno joked. "I find that interesting."

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