The "battle rounds" begin and the coaches enlist the help of music industry professionals to offer their knowledge and skill as advisers. Christina Aguilera teams up with Jewel and Lionel Richie, Adam Levine with Alanis Morissette and Robin Thicke, Cee Lo Green with Kenny "Babyface" Edmonds and Ne-Yo, and Blake Shelton with Kelly Clarkson and Miranda Lambert. In this phase the coaches pit two of their own team members against each other in a dueling duet. After the vocal face-off, each coach must choose which vocalist from their team is the strongest and advance them to the live shows. Carson Daly ("Last Call with Carson Daly") hosts. Christina Milian ("Be Cool") serves as Social Media Correspondent.