Jason Aldean has plenty of duets in his repertoire, but his collaboration with Carrie Underwood, "If I Didn't Love You," is among his biggest. The midtempo duet is full of heartache, and finds both sides of a former relationship having trouble moving on — because each still loves the other.

Kurt Allison and Tully Kennedy, two of Aldean's band members, co-wrote "If I Didn't Love You" with John Morgan and Lydia Vaughn. Below, Aldean shares the story behind the song, in his own words.

"If I Didn’t Love You," that song came together — it was kind of a last-minute thing.

We were lookin’ for songs to possibly have for a duet on the record. We didn’t really have the song — we had a couple of songs that people had sent that I hadn’t fallen in love with — and so a couple of guys in my band went and decided they wanted to try and focus on writing a duet. And they went in for a couple days and came back with this song. I just I thought the song was great.

We just didn’t have a duet partner for it yet, so I went in and cut the song anyway, I just — I was like, "Man, if we can’t find somebody to sing on this, the song’s too good to not record." So, I cut the song, and in the meantime, we were — we had a short list of people we wanted to reach out to, and Carrie was at the top of the list, so we sent it to her and got basically an immediate response back from her that she loved the song, was interested, and then, all of a sudden, it was kinda like a rocket from there.

It was like, we cut it, she was in the studio the next week, we cut her vocal, mixed it, mastered it, did everything. I mean it all, from the time the song was written until it was completely finished, was literally about three weeks. So, it happened pretty quick, and was something that we were looking for for the album and really needed, and something that I hope will be a special song and a special song for this album.

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