Nick Jonas is getting into coaching. He'll be sitting in one of the big red chairs for season 18 of NBC's "The Voice" next spring.

Jonas made the announcement Monday on Ellen DeGeneres' talk show along with his brothers. He'll join Blake Shelton, Kelly Clarkson and John Legend.

Actually, it was Ellen that made the announcement in a playful way to undercut Jonas' announcement. She first showed a video message from Shelton.

Nick Jonas! How you doing, buddy?” Shelton said. “I heard that you’re going to be a new coach on 'The Voice' and I wanted to, first of all, say congratulations, I guess. But second of all, I wanted to voice some concerns that I have. I’m going to have to look through the rules because this is my TV show. I’m not even sure if you’re old enough to be a coach on The Voice, but I’m certain that you’re going to get your butt kicked, buddy.” 

Jonas is 27. Shelton is 43.

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Next was Clarkson.

"I just want to say congratulations. I do definitely feel like the two Texans should maybe team up and form an alliance. I’m just saying," Clarkson said.

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Legend had the same idea, but to take down Shelton.

"Our mission is to destroy Blake Shelton. We have to form an alliance. Me, you, Kelly. We team up. We beat Blake. Nothing else matters," Legend said.

Jonas said he would kick Shelton's butt -- except he didn't say butt.

Then DeGeneres got the last laugh. As Jonas was talking about his upcoming endeavor, a cowboy popped out of the end table next to him, causing Jonas to scream. Scaring her guests like that is an ongoing gag for DeGeneres.