Even the pros can get thrown off sometimes.

Josh Gad opened up about which celeb threw him off his game while performing in Book of Mormon on Broadway.

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While speaking to Zane Lowe on “Song For Life“, Gad finally revealed who made him forget his lines.

“I have not ever officially [confirmed] that, but, god, I got nothing to lose now. It was the lead actor on a show called ‘Entourage’…Adrian [Grenier]. And I was, let’s say, really f**kin’ pissed off. So Adrian, the next time you’re out there in a dark theatre with a bunch of people onstage performing for you, I would ask for a little bit more respect. And I promise to show you the same respect when I watch you on a stage.”

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He added, “All joking aside, I hope you’re doing well, Adrian! I still love you, I still love you very much.”

Grenier has not responded.