A diva fight took place recently, and it was not between Whitney and Aretha, but Jeremy Piven and Chris Kattan. I know, what? Really? Why?

Both were appearing on Alexa Chung’s MTV talk show. They were backstage when Kattan asked Piven, “So, what are you here to promote, your Broadway play?” You may wonder why this innocent question/joke would unleash such a spazzed-out tirade from Piven. This is because “Piven left Speed the Plow last December after suffering mercury poisoning from bad sushi and is now in a legal battle with the show’s producers who believe the actor made up the plan to get out of his contract,” reports MSNBC.

The Entourage star's response to Kattan was, “Well, what are you here to promote? Mango?” (That crazy SNL character, a monkee/stripper) The two began yelling at each other until Piven said something “very personal” about Kattan’s career.

An insider said, “He (Kattan) said, ‘Whoa, man – I though we were just fooling around here?’

“I’m getting sued for that shit! It’s not funny!” Piven reportedly shouted before running to the green room and slamming the door. Yes like a child, and no I am not making this up.

The insider said, “Chris felt really bad about the whole thing, so about 15 minutes later he tried to approach Jeremy again to apologize, to tell him he was just kidding and that he didn’t mean to offend him in any way. But Jeremy wasn’t having it at all. He slammed the door in Chris’s face again.”

Piven’s rep denied the whole fight ever happened and that they were joking around with each other. His rep said, “Jeremy and Chris did see each other at MTV and they were joking around backstage before a talk show appearance, as many actors do. If it was interpreted as a fight, someone wasn’t paying attention.”

On the other side, Kattan’s publicist said that the two did fight and that he tried to apologize to Piven.

Hmm, who to believe? I think I may have to side with Kattan on this one. Piven needs to chill.