Keith Urban had better learn to duck. The singer recently left his gig on the Australian version of 'The Voice' to become the first country star to judge 'American Idol,' only to land square in the middle of a feud between fellow newcomers Mariah Carey and Nicki Minaj.

TMZ reports that Minaj and Carey have been at odds since virtually the second they met, but things culminated in an on-set meltdown Tuesday, shutting down auditions in Charlotte, North Carolina after the two divas got into a furious verbal altercation, which was caught on tape. The fight apparently began after the pair disagreed about a contestant's performance, then rapidly escalated into a profanity-laced tirade which Minaj directed at Carey.

"Think it’s a joke? Think it’s a joke? Think it’s a joke?" an out-of-control Minaj is heard screaming in the clip (see below). "Say one more disrespectful thing to me, if you say one more disrespectful thing to me -- off with your head!"

Carey doesn't back down, replying, "I am not being disrespectful," which seems to goad Minaj even more. "Don’t tell me I'm insecure, don’t tell me I'm inadequate," she rages. "I don’t feel inadequate. You’re the insecure one sittin' up there running down her resume every five minutes." At that, Carey moans, "Oh why, WHYYYY do I have a three-year-old sitting around me?”

Randy Jackson attempts to calm the two women down, while the hapless Urban -- who is seated directly between the two warring judges -- shifts awkwardly in his chair before literally throwing his hands in the air in frustration. TMZ reports that production closed down for the day to let the women calm down.

Mariah Carey recently denied rumors of a feud, saying, “How are we gonna feud in two days? A feud takes a little longer to spread out [than that]. It’s fun, it’s music, it’s singing, it’s laughter!”

Unfortunately, the time so far on the 'Idol' set doesn't look like much fun or laughter for Keith Urban -- who really ought to consider sitting on the end from now on.

Watch Nicki Minaj and Mariah Carey's Confrontation