Adam Levine is terrified of Shakira.

The Maroon 5 singer will be joined on 'The Voice' by the singer and Usher next season when they replace Cee Lo Green and Christina Aguilera but he has no plans to subject her to any initiation ceremonies because he knows the pregnant star is more than a match for him.

He said: ''[Fellow coach] Blake Shelton and I don't have it in our hearts to do anything terrible and I know Shakira, she could knock me out.''

While he is excited about working with Shakira, Adam will miss Christina, despite their bickering on the show.

He told Us Weekly magazine: ''We never hated each other. It was just silly bickering, like brother and sister. That's in the past, I'll miss her next season.''

Adam recently hit out at criticism of Christina's fuller figure.

He said: ''It's not cool. I've never liked it. I think it's horrible and I'll totally defend [Christina] when people say things like that because it's no one's business.

''The one thing about the culture right now, celebrity culture particularly, is people feel like they can just say nasty things about other people whether it's Christina or whether it's me. Of course I have her back and of course I defend her.''