The Cadillac Three had some pretty big shoes to fill during their recent appearance at the Grand Ole Opry, and they performed like ... well, rock stars. The country-rock trio sang a stripped-down acoustic version of "Meanwhile, Back at Mama's," Tim McGraw and Faith Hill's 2014 duet.

The Cadillac Three's lead singer, Jaren Johnston, co-wrote the hit tune with Tom Douglas and Jeffrey Steele, and the singer-songwriter admits that no one was more surprised than himself that Hill recorded the song with McGraw.

“[We] just wrote a folky thing,” Johnston recalls. “[Big Machine Label Group President] Scott Borchetta said, ‘You know it’s going to be a duet, right?’ And I was like, ‘Who are they going to get?’ I had no idea. He’s like, ‘Faith’s going to sing on it.’ I was like, ‘Score! Touchdown!’”

Even McGraw didn't originally hear "Meanwhile, Back at Mama's" as a duet, but the response from his wife quickly changed his mind.

“I got home, I walked into the house, and I said, ‘Faith, you’ve got to hear this song,’” McGraw says. “So I played her the song, and when it got to the end and it said, ‘Me and you back at Mama’s,’ a flood of tears just came down from her eyes.

“I said, ‘Not only am I going to cut, but you’re going to sing it with me,’” he adds. “And that’s how it was born, right there.”

"Meanwhile Back at Mama's," from McGraw's Sundown Heaven Town album, was nominated for Grammy Award, for Best Country Song, in 2015, as well as an ACM Award, for Vocal Event of the Year.

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