NBC’s Emmy Award-winning musical-competition series "The Voice" has confirmed Coldplay frontman Chris Martin as the key adviser for the current season. As part of a new format change, Martin will serve as a mentor for the artists on each of the four teams, a "Voice" first.  

The newly created The Battles: Round Two will begin Monday, March 31 and pit the remaining artists from each team—all previous winners and stolen artists—against one another to perform an agreed-upon song. Both artists will sing for their coach’s approval in hopes of moving forward to the Playoff Rounds.

Martin advised each of the The Battles: Round Two performers on vocal techniques, stage presence and the importance of tailoring songs to fit their persona and strengths. These artists will continue to try and earn the support of their respective coaches, who will be forced to decide who will move on to the Playoff Rounds. Each coach will have the opportunity to strategically steal one more artist in this round.