The Voice contestants Ethan Lively and Avery Roberson faced off with a James Otto cover during their Battle Round performance on Monday night (March 29). The country singer's 2008 hit had guest coach Kelsea Ballerini grooving along.

Ballerini, in fact -- filling in for an ill Kelly Clarkson -- later admitted that she felt like the performance was a serenade for her. "I'm blushing!" she said, fanning herself with her hands and adding, "I'm flattered."

Lively and Roberson also earned nods of approval from coaches Blake Shelton and John Legend; added coach Nick Jonas as they were performing, "This is awesome." Indeed, the two aspiring stars' voices melded well, and they played off each other during the song, too.

"That's what steals are made for!" Shelton said approvingly as they finished the performance. Legend and Jonas, meanwhile, remarked on the low range needed to sing the song well.

"I can't even get close. I feel like half a man," Jonas joked, adding, "Really impressive performance from both of you" and telling Lively and Roberson that their duet made him feel as though he was down at Billy Bob's in Fort Worth, Texas, drinking beer and line-dancing, "which is something I've actually done before."

"Really?" Shelton questioned. When Jonas affirmed that he was telling the truth, the country star added, "I wish we had that video."

As both Lively and Roberson are on Shelton's team, it was up to him to deliver the final judgement and decide which singer would stay in the competition. The country superstar complimented both men before declaring Lively the winner of the battle.

"I didn't expect that at all!" Lively confessed later.

Roberson's initial audition earned him a four-chair turn, though, so it only makes sense that another coach used a steal to keep him in the competition. It was Ballerini, on behalf of Clarkson, who made the move, sharing that the two had been texting and Clarkson told Ballerini to get Roberson for her team.

Now in its 20th season, The Voice will continue its Battles Rounds on Monday (April 5). The show airs on NBC at 8PM ET.

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