Former American Idol champion Clay Aiken has admitted he had plastic surgery and also weighed in on Rihanna's singing abilities in a recent television appearance.

Aiken told Andy Cohen of "Watch What Happens Live" on Bravo on Tuesday that he underwent a procedure.

"I had operative surgery on my jaw for a TMJ thing and I had them suck the fat out of my chin while they were in there," he said. "I was like, 'You know what, while I'm already down, go ahead and take the vacuum in there and suck the fat out of my chin."

Also on the program, he was asked what he thought about contestants on America Idol recently and what current pop stars would not make it past the show's first round.

"Oh God there are too many, too many ... I've stopped listening to them because they can't sing," he said.

After mulling it over he came up with one.

"Rihanna has some pitch problems for sure," he said smiling.  

Tags: Clay Aiken Rihanna