Rascal Flatts' upcoming album, Back to Us, includes a duet with Season 10 American Idol runner-up Lauren Alaina, on the powerful song "Are You Happy Now." A pensive look back at a former relationship, "Are You Happy Now" gives Alaina a chance to show off her powerful voice -- but, as it turns out, she wasn't the first artist that Rascal Flatts asked to sing on the track.

"We wrote the song four years ago and reached out to Taylor Swift, for the Rewind record," Jay DeMarcus tells The Boot, "and she said no. And so, we put the song on the back burner for a long time and circled back around this time, cut a new track on it and sort of waited to see who we felt like would be the top of that list to go toe-to-toe with Gary [LeVox], because it’s no easy task to find a singer to get in a booth with Gary and match his vocal prowess."

When the Flatts' last studio album, Rewind, was released in May of 2014, Swift was only a few months away from announcing her transition to pop music and releasing 1989, her first full pop album.

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It's unclear if Swift's own career plans factored into her decision to decline Rascal Flatts' duet invitation, but the two acts go way back: Both are part of the Big Machine Label Group's roster of artists -- the Flatts since their 2010 album Nothing Like This and Swift since her debut album in 2006 -- and Swift opened for Rascal Flatts early in her career, on their Me & My Gang Tour, famously taking over for Eric Church after he was kicked off the trek for playing too long.

When reconsidering "Are You Happy Now" for Back to Us, Rascal Flatts say, Alaina was the only artist they asked to sing the song's female part -- and they couldn't be happier with the finished product.

DeMarcus produced all 13 tracks on Back to Us, although with LeVox and Joe Don Rooney in the studio, it was more like a party than a day at the office.

“The three of us in the studio, it’s hard to get any work done, because we have a good time when we’re hanging out together and making music. It’s our favorite thing to do,” DeMarcus shares. “It’s a huge honor and a huge responsibility, and I don’t take it lightly.”

Back to Us will be out on May 19. The record is available for pre-order on Amazon and iTunes.

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