Cody Johnson's as-yet unreleased duet with Carrie Underwood has been a long time in the making. As a matter of fact, the singer says he first got the idea for the collaboration years ago.

"From the moment I heard the song — and this was six years ago — I wanted to record it and I wanted to do a duet with Carrie, because I heard her voice on it," Johnson told press backstage at Nissan Stadium before his CMA Fest set on Friday (June 9).

Johnson goes on to say that another country artist — who Johnson didn't name — wrote this song, and at first, it was earmarked for that artist to record. He ultimately decided not to cut it, and the track then got diverted towards Underwood, but wound up not being a fit for the record she was recording at the time.

"And I said, 'Whatever happened to that song that that guy wrote?' They said, 'Well, it never got recorded.' And I said,'I want Carrie Underwood on it,'" the singer continues.

He didn't have a Plan B for who he might want to sing it with — it was Underwood or bust, Johnson goes on to say.

"I said I didn't wanna record it unless I could have Carrie on it. And you know, I've loved Carrie's music, but it's not like — I don't have her poster on my wall, you know? But when I heard this song, I heard her voice, and I just knew that it was gonna work out," he explains.

Johnson also says that as soon as he and Underwood finally got in the studio, his instinct that it had to be her paid off.

"We had never sang together. So when we got in the room and we start[ed] singing together, it was like family harmony," he gushes. "The only way I can describe it is kinda like the way it was growing up singing with my mom. It just instantly fits and meshes. And it's really interesting to me, because my voice and her voice are really drastically different. But put together, they make a very, very unique sound."

Johnson has said that he's working on another double album, called Cody Johnson: Leather. That project doesn't have an official release date yet — the singer has said it could be coming out late in 2023, or perhaps in 2024 — and he doesn't have an exact release date for his Underwood duet yet, either.

"I'm excited for it to come out. Not sure when it is. We're kinda holding the ace card close to the sleeve," he adds.

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