It’s the un-funniest feud in Hollywood – two comedians and former friends now pitted against each other.

“He threatened my life,” Jon Lovitz said about the fight that led to Jon punching Andy Dick in the face. “Everybody’s thanking my for beating him up.”

Jon is talking about the fight for the first time, telling “Extra” the full story behind the long-simmering battle that exploded into a violent brawl at Hollywood’s Laugh Factory last week.

“I shoved him vigorously a couple of times against the wall,” Jon explained.

Jon claims the feud began 10 years ago when he accused Andy of re-addicting Phil Hartman’s wife Brynn to cocaine, just months before she shot Phil – taking away Jon’s good friend.

“He’s trying to say now that Brynn gave him cocaine, because he’s a pig and that’s not what happened and everybody knows it,” Jon blasted.

It turned even uglier when the two bumped into each other at a restaurant a year ago.

“He looks at me and says, ‘I put the Phil Hartman hex on you. You’re the next one to die,’” Jon alleged.

Then, Andy turned up at Jon’s regular Wednesday night Laugh Factory stand-up performance this week.

“I was just waiting for him to say he was sorry, and he didn’t. I lost my temper,” Jon said. “And if I see him again I would do the same thing.”

He added, “He’s just a pure, unadulterated jerk.”

Now Jon has a warning for Andy, whose troubled past includes DUI and drug arrests: “I think he should avoid me like the plague.”

“Extra” tried to get Andy’s side of the story, but his reps didn’t return calls for comment.