Tyler and Jennifer Lopez will join existing judge Randy Jackson on the judges' panel when the programme returns for a 10th season next year.

In an interview with Entertainment Weekly, Rock said Tyler had tarnished his legacy by joining the show.

"I think it's the stupidest thing he's ever done in his life," he said. "He's a sacred American institution of rock and roll, and he just threw it all out the window. Just stomped on it and set it on fire."

Rock added: "I think whoever's advising him ... we should bring back the guillotine, or whatever they call that thing.

“And if it was himself, he needs some serious counselling. I love him to death, but I gotta speak the truth."

Former American Idol judges Ellen DeGeneres, Kara DioGuardi and Simon Cowell all stood down after the ninth seasion. Audtions for contestants for 2011 are ongoing.

(by Jason Gregory)