Tension has started to creep in on the American Idol set as Nicki Minaj goes in and verbally attacks fellow judge Mariah Carey!

Sources say Nicki even took it a step further off camera and threatened to “knock out” Mariah!

Transcript:

Nicki  Get this shit in self control.  Get in control.  Get in control. Randy  Settle down, settle down Nicki  Don’t lose your head.  Don’t lose your head (inaudible).  Don’t tell me I’m a gangster. Nicki  (inaudible) every 5 minutes.  So every time you patronize me, I’m-ma take it back, and if you’ve got a fucking problem, handle it. Nicki  I told them I’m not fuckin’ putting up with her fucking highness over there.  Figure it the fuck out.  Figure it out. Nicki  I’m not gonna sit here every fucking minute to have you come down and harass me every minute everyday.