Keith Urban may sometimes serve as the referee between warring fellow 'American Idol' judges Mariah Carey and Nicki Minaj, but that doesn't mean it's all sweetness and light for the country superstar. In fact, 'Idol' producer Nigel Lythgoe says Urban has sparred with all of the judges on the panel, including a huge blow-up with Minaj.

The auditions for the upcoming season had barely gotten underway when Carey and Minaj clashed in a profanity-laden confrontation that went viral after it was leaked online. Urban was literally caught between the two women as Minaj directed a tirade at Carey, and he later said that he "was the U.N." in the situation, adding, “I gotta say, I love working with passionate people. I love artists, and I like everyone just sort of expressing themselves. It’s a very alive, very invigorating work environment.”

In a conference call with reporters, Lythgoe described the country superstar as the "scratching post between Mariah and Nicki" (quote via USA Today), but also said that the country judge has had a few heated moments of his own, including a "big one with Nicki." He said that's due to each judge's different vision of what they want from a contestant.

"Nicki is looking for an artist," Lythgoe noted. "Mariah is looking for the complete singer-songwriter. Randy [Jackson] is looking for somebody that sings on pitch. Keith is not just looking for a country singer. He is looking for an instrumentalist, a good singer and somebody that can capture that magic -- charisma, if you will."

Season 12 of 'American Idol' premieres Wednesday, Jan. 16 at 8PM ET on Fox.

More From 106.5 WYRK