The Muppets actor revealed that he recently became starstruck after walking the red carpet at an event which was also attended by stars such as Angelina Jolie and Brad Pitt.
"One time I was on a red carpet and Brad Pitt and Angelina Jolie came up to me and they said, 'We just watched [Forgetting] Sarah Marshall. We just wanted to say hi. Great job!'" Segel recalled in a new interview on The Tonight Show with Jay Leno.
"And my response was, 'Oh, my God! It's you!'"
Segel recalled a similar incident which took place during his introduction to former US president Bill Clinton, adding: "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. I know he was charming. I don't think I said anything at all. I'm bad with this stuff."
Segel will host the November 19 episode of Saturday Night Live, with Florence + the Machine appearing as the musical guest.
Watch The Muppets Bollywood trailer below: