Monday night marked the start of the battle rounds on NBC's The Voice . During this stage of the competition, each coach pits two of his or her artists against one another in a duet. The coach then must choose a winner.
Afterward, the other coaches have the opportunity to "steal" the losing artist. Each coach has two "steals" he or she can use during the battle rounds.
Adam Levine , Blake Shelton , Shakira and Usher each enlisted the help of a mentor for the rehearsals leading up to the battle round performances. Adam was joined by Lady Antebellum 's Hillary Scott ; Blake had Sheryl Crow by his side; Shakira brought in Good Charlotte 's Joel Madden , a coach on the Australian version of The Voice ; and Usher teamed up with rapper and producer Pharrell Williams .
In the first battle of the night, two of Adam's protégés faced off: Amber Carrington , 19, and Sasha Allen , a 30-year-old mother of two. They sang the Pink tune "Try." Adam remarked that it was one of the best battle rounds he's seen on the show to date. Though he felt both artists were inspirational, he declared that Amber was the winner.
Sasha quickly earned a reprieve when both Usher and Shakira made a bid to steal her. She was allowed to choose which coach she wanted to join; she selected Shakira over a flabbergasted Usher.
The next battle featured Team Shakira's Garrett Gardner -- the 17-year-old who delivered a reggae version of The White Stripes ' "Seven Nation Army" during his blind audition -- and J'Sun . They duetted on The Heavy song "How You Like Me Now?" Shakira was moved by Garrett's charisma, and added that J'Sun did an amazing job. Garrett got the win, and J'Sun was not picked up by another coach.
Up next were two of Blake's artists: Holly Tucker , the 19-year-old member of the Baylor University marching band, and Michelle Raitzin of Long Island, New York. The women belted out Carrie Underwood 's "Blown Away." Blake said he was "sick" that he had to make a decision. He asked host Carson Daly if he could choose both. When Daly replied in the negative, Blake jokingly shot back, "Screw you!" Holly advanced, while Michelle headed home.
Usher prepped for a duel between two Texans: Jess Kellner and Taylor Beckham . They performed "You Know I'm No Good" by the late Amy Winehouse . Usher said he was looking for strong stage presence from both artists. He then cautioned, "I can't say you both came out here and 100 percent lit it on fire like I know you can...the work is only going to get harder." Jess moved on, and the show said goodbye to Taylor.
Team Blake artist Christian Porter , a 21-year-old from Pennsylvania, returned to take on the country duo The Swon Brothers . Together, they covered Tom Petty 's "I Won't Back Down." This was the second time The Swon Brothers performed a Petty song, following their rendition of "American Girl" during their audition. We'll see The Swon Brothers again; the same cannot be said of Christian.
Judith Hill , a former background singer for Michael Jackson , and Karina Iglesias closed night one of the battle rounds with James Brown 's "It's a Man's Man's Man's World." Blake questioned Adam for pitting the two artists against one another, and marveled, "Battles shouldn't sound this good." For the second time, Adam said it was the best battle round he's seen. Judith was named the winner. Shakira then swooped in and stole Karina.
The battle round continues with a one-hour episode airing Tuesday night on NBC at 8 Eastern time.
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