Coldplay's Chris Martin joining "The Voice"

Coldplay frontman Chris Martin is bringing his expertise to "The Voice."

NBC said Wednesday that Martin has been named a "key adviser" for the music competition series. He'll participate in the music competition's "battles" round that begins March 31, advising singers on vocal technique and stage presence.

In a first for "The Voice," Martin will serve as a mentor for artists on all four of the coaches' teams.

The newly created "The Battles: Round Two" will pit the remaining artists from each team against one another to perform an agreed-upon song. The singers are vying for the attention of their coaches -- Blake Shelton, Adam Levine, Shakira and Usher -- who must decide who gets to move on in the show.

"The Voice" has established itself this season as the most popular of the music shows, eclipsing the long-running champ "American Idol" on Fox.

The guest role is good promotion for Martin and Coldplay, which is releasing a new album in May.