'The Voice': Kelly Clarkson and Niall Horan Get Emotional Over a Bon Iver Battle

Which singer 'broke Kelly's heart' on Monday?

Niall Horan has officially coached his first Battle on season 23 of The Voice -- and it was a doozy!

The Battle Rounds kicked off on Monday, and Team Niall immediately had an emotional pairing that left the coaches all in their feels. The rookie coach matched up young performers Gina Miles and Kala Banham on a cover of Bon Iver's "Skinny Love" that brought tears to Kelly Clarkson's eyes almost immediately.

Kelly praised both singers' impressive tone, but admitted she was "gravitating" toward Kala -- in part, because Niall blocked her from landing the singer during the Blind Auditions.

"I love your voice," she praised. "That broke my heart, it was so beautifully sung."

"There was one word she said and I almost cried," Kelly also admitted. "I was like, 'Don't go there! Go dead inside!'"

Blake Shelton and Chance the Rapper, however, were both leaning toward Gina's dynamic voice -- noting that her sometimes-imperfect pitch made the performance more "interesting" and would be perfectly suited for a record.

As for their own coach, Niall admitted that he "didn't sleep a wink" the night before, due to anxiety over the Battles, but ultimately, he named Gina the winner -- and was equally thrilled when Kelly did her part, and stole Kala to her own team.

"I stole Kala because I've been waiting for her," Kelly shared. "I remembered her from the Blinds and I'm so glad she's Team Kelly -- watch out, Niall!"

Check out the full Battle below!

ET spoke with the season 23 coaches ahead of the premiere, who all shared how excited they were to be on the show for The Cowboy's last go-round.

"I texted him," Kelly shared. "If he was gonna do a last season, I wanted to make sure I was there."

However, the talk show host insisted that she won't be letting nostalgia affect her competitive nature.

"If [Blake] wins, I am very happy for him, because that is super cool to win on the last season and he's literally the show, from its conception," she conceded. "But, like, I'm not, like, rooting for him to win. I'll be happy for him if he does, but I'm obviously trying to win myself."

As for the show's new coaches, Niall and Chance said they were ready to put in the work against the Team Blake dynasty.

"It's been awesome," Chance said of joining the show. "Kelly's very, very sweet, very nice to me. And Blake is... here."

The Voice airs Mondays at 8 p.m. PT/ET and Tuesdays at 9 p.m. PT/ET on NBC.