Gwen Stefani has an ace up her sleeve on "The Voice": the mom card.

Stefani found herself going head-to-head with fellow coach John Legend during the first round of Battles on Tuesday night. During the Battles round, each coach pairs up their singers for a series of vocal battles that will determine which contestants will continue on their teams.

Team Niall singers Lennon VanderDoes and Tanner Massey faced off with a tender rendition of the Billy Joel ballad “She’s Always a Woman.”

Massey was an immediate standout to Stefani with his magnetic stage presence. “I am dead in love with you. You are just magical,” Stefani told Massey. “It’s hard to not want to just keep watching you.”

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While coach Niall Horan was charmed by VanderDoes’ “captivating” tone, the Phoenix singer’s duet with Massey left him feeling torn.

“This is one of the battles where I’ve been really battling with myself,” Horan said. “And now I regret putting you in the same pairing.”

Horan declared VanderDoes the winner of the battle, sending Massey’s standing in the competition into jeopardy.

“I’ve always been super attracted to really interesting tones,” Horan said of his decision. “There’s nobody in this competition that has a tone even remotely near (VanderDoes), and that makes him a very, very dark horse.”

But before Massey could say his goodbyes, Stefani and Legend hit their steal buttons for a chance to bring the Oklahoma vocalist onto their teams. “I think America’s going to love you, so I feel like we could go pretty far together,” Legend said.

“You have something in you that you’re showing us that we want more of. What I could do to help you bring even more of that out is put a mirror up and highlight,” Stefani told the 19-year-old singer. “And I’m a mother of three boys. I have a son about your age, and he’s a singer. I feel like I could just hug you into the winning spot.”

Stefani’s maternal instincts proved to be right on the money. Massey chose to join Team Gwen in the end.

“I beat John Legend, and I can’t believe I have Tanner on my team,” Stefani said. “It’s so exciting.”

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