On Tuesday night's "Idol," after Didi Benami performed "What Becomes Of The Broken Hearted," a performance she was eventually sent home for, Simon slammed her rendition, and in doing so, slammed Len's show.
"If you listen to one of those dancing shows, they always have a singer murdering a song on it," Simon said. "That's what it kind of — if you've ever watch it – that's what it kind of sounded [like]."
The direct jab at the "DWTS'" live band didn't sit easy with Len.
"He's bitter. Honestly, he's bitter. Simon Cowell is bitter," a grinning Len told Access Hollywood's Billy Bush on Thursday. "As far as I'm concerned, those singers are genius. When you watch what they have to go through – hip-hop, light operatic, anything thrown at them, they're brilliant. I love that band and I love those singers and I didn't mind Simon Cowell until this point.
"When I take these clothes off, you can't believe what's under this… honestly, ripples! And he's gonna get the full force, right in the navel. It's gonna be a navel attack," Len added jokingly.
Len wasn't the only "Dance" judge though to take notice of Simon's comments.
Simon's former "Idol" executive producer, Nigel Lythgoe, who is now a judge on "So You Think You Can Dance," took to his Twitter twice on Thursday, to Tweet that the currently engaged Brit will soon have to dance, and when he does, Nigel has no doubts it will be as bad as Simon thinks the dance show singers are.
"He may be leaving "Idol" but he's joining the "All-Stars" before his wedding, representing the genres of Wacking and Vogueing- SIMON COWELL," Nigel wrote.
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