Django and Jimmie, the new album by Merle Haggard and Willie Nelson, includes a brand-new song, "Missing Ol' Johnny Cash," that Haggard wrote as a tribute to his late friend.

"Johnny Cash and Merle, their history goes back," producer Buddy Cannon explains in the video above. "I think the first time Merle saw Johnny Cash, he was an inmate in one of the prison shows that Cash played. They were friends all the way up until the end."

The Hag says that the song came about organically, and he wasn't even sure of the chord progression until they got into the studio.

"It came about around the time we were trying to put some songs together," Haggard explains.

Adds Cannon, "He just had the lyric, and he created the arrangement on the spot."

In the tribute tune, Haggard sings, "Johnny Cash was a friend of mine / I knew him well for a mighty long time / We shared the stage for many a show / Broke my heart to see him go / Cash had the fire of a thousand men / Lovin' life was his greatest sin / Treated his fans like the next of kin ... I'm missing ol' Johnny Cash."

Then, Nelson takes a turn: "Johnny Cash wore black attire / He fell into that Ring of Fire," he croons. "He came up swinging like a Boy Named Sue / I'm missing ol' Johnny Cash."

This entire new project is in honor of two of Haggard and Nelson's biggest musical heroes.

Django Reinhardt and Jimmie Rodgers were very influential in both our careers,” Nelson explains. “I listened to both Jimmie and Django growing up, and I know Merle did, too.”

Django and Jimmie is now available on iTunes and Amazon.

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