Nicki Minaj and Mariah Carey Already Fighting on 'American Idol'

Well, that didn't take long.

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It's no secret Mariah Carey was fuming when she heard FOX hired rival Nicki Minaj to sit beside her at the American Idol judging table, and it appears the two divas are already cat scratching.

Reports surfaced today that during the first taping on Sunday, Mariah and Nicki were visibly upset with one another.

"When Nicki started critiquing a contestant, Mariah would interrupt — not once, but many times," reports the source. "Each time Mariah interrupted, Nicki fought back by loudly talking over Mariah...These girls just don't like each other."

Sounds like it's going to be a long couple of hormonal months. Keith Urban and Randy Jackson better fasten their seatbelts.

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When it was first revealed that Nicki made the American Idol judging short list a few weeks ago and a FOX producer called to tell Mariah, she reportedly slammed the phone down in anger.

A source close to the singer said she didn't want to compete with a much younger woman and would rather be the only female like Jennifer Lopez.

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