11/29/2009 05:12 am ET Updated Dec 06, 2017

Matt Damon To Adrian Grenier: 'Go F*** Yourself' (VIDEO)

While shooting a PSA for his clean water organization OneXOne, Matt Damon lost his cool and went on an F-bomb heavy tirade against Adrian Grenier.

'Dont get f***ing smart dude. If you don't want to do it walk away," he says. "F** you. Go f*** yourself!"

Grenier continues to fumble his lines while Jeremy Piven tries to play peacemaker.

Surprise, not for real! The stunt is a promotional bit for the season finale of 'Entourage' on October 4, when Damon makes a cameo to promote his real-life charity.


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