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As season 2 of The Voice premieres, coach Adam Levine still has to contend with those pesky American Idol comparisons.

On Friday's episode of The Ellen DeGeneres show, Levine -- who helped launch the career of season 1 Voice winner Javier Colon -- answered back to one of his more vocal detractors: American Idol judge Randy Jackson.

Levine was especially offended when Jackson, 55, told reporters at January's Television Critics Association press tour that The Voice was for "second chance people." "The winner of The Voice, I will remind you, was an artist who had a deal at Capitol Records for several years, a failed contract," he sniped, referring to Colon.

"Shame on Randy Jackson for saying that," Levine, 32, told DeGeneres, who served as an Idol judge herself in 2010. "Because he of anybody should know that if you're in this business you need second, third, fourth and fifth chances. So we love and embrace having that being part of the show."

This isn't the first time Jackson and Levine have gotten into a war of reality TV words.

Last summer, Levine argued that The Voice's rejects could "win American Idol," but Jackson wasn't buying it.

"Look, none of these other shows could exist without somebody forging the path before them," Jackson told The Hollywood Reporter of shows including The Voice, which counted season 2 Idol finalist Frenchie Davis among its strong season 1 contenders. "I'm happy to say that Idol did that and paved the way."

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