When "Whisperin' Bill" Anderson and Jamey Johnson co-wrote their newest collaboration "Everybody Wants to Be Twenty-One" together, they weren't intending to record it as a duet. In fact, they weren't intending to record the song at all.

"We just intended maybe to pitch it to Willie Nelson," Anderson says in the video above, "or maybe George Strait, or somebody like that."

As Anderson sat with the song, however, he realized that the tune needed two singers, from different generations: "The more I got to foolin' with it, listenin' to it, thinkin' about it, I thought, 'Well, this needs to be an older guy and a younger guy ... looiin' at it from each point of view,'" he explains. And who better to carry out that vision than the song's writers themselves?

Readers can press play below to hear "Everybody Wants to Be Twenty-One." The song is the first single from Anderson's forthcoming new album and is premiering on The Boot. Backed by a simple melody of quiet drums and pedal steel, Anderson and Johnson trade verses and lines before harmonizing on the final chorus.

"Everybody wants to be 21 / Full of life and lively, full of fun," they sing. "The young wish they were old, and the old wish they were young / Everybody wants to be 21 ..."

Anderson's new album, simply titled Anderson, will be his 72nd career album. The Grand Ole Opry, Songwriters Hall of Fame and Country Music Hall of Fame member co-produced the 11-track project with Thomas Jutz and Peter Cooper. In addition to Johnson, Anderson includes collaborations with John Paul White, Paul Overstreet and more.

Anderson is due out on Sept. 14.

Listen to Bill Anderson and Jamey Johnson's "Everybody Wants to Be Twenty-One"