The knockout rounds are coming to an end on The Voice, but that doesn’t mean the bickering between the coaches is slowing down one bit!

On Monday’s show, Brandon Royal, a Team Gwen hopeful, belted out Bob Marley’s “Redemption Song,” and while he wasn’t selected to move on to the live shows, his song choice led to a hilarious moment between the coaches when Blake Shelton admitted to not being familiar with the iconic ballad.

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“Wait, you don’t know ‘Redemption Song?’” Alicia Keys asked Shelton incredulously during a behind-the-scenes moment. “You have to know… everyone knows ‘Redemption Song!’”

“I know ‘One Love,’” Shelton admitted.

The confession cracked up Shelton’s girlfriend and fellow coach, Gwen Stefani, but Keys was taking her musical mentorship very seriously.

“When you leave here, listen to the greatest hits of Bob Marley,” she instructed the country crooner. “You shouldn't even call yourself a musician.”

“That’s on my girlfriend,” Shelton said with a laugh. “I feel like that's her responsibility and she hasn't followed through. Come on.”

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Monday’s episode also saw the unfortunate elimination of fan favorite contestant Jack Cassidy, who failed to make the live shows despite his soulful cover of “Unsteady” by X Ambassadors.

“Alicia I'm so honored and humbled to have worked with you,” said the musical legacy, who is the nephew of David Cassidy and the grandson of Partridge Family star Shirley Jones. “You're amazing.”

See more from this season of The Voice in the video below.

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