There's a host of star power behind the King of the Road: A Tribute to Roger Miller album, a portion of which comes from the legendary trio of Willie Nelson, Kris Kristofferson and the late Merle Haggard, who are all featured on a cover of "Old Friends."

Recorded prior to Haggard's passing in 2016, the iconic artists turn the song into a waning country ballad where each of their voices get a moment to shine and pay honorable homage to a fellow legend.

The tribute serves as a walk down memory lane for Nelson, who was a featured vocalist with Miller and Ray Price on the original version of the song, which was released in 1982 and made it to the Top 20 on the Billboard Hot Country Songs chart. Though composed of only three short stanzas, "Old Friends" feels more like a poem put to music, as Nelson, Kristofferson and Haggard capture the essence of the song beautifully: "Old friends / Looking up to watch the birds / Holding arms to climb a curb / Old friends / Lord when all my work is done / Bless my life and grant me one / Old friend at least one old friend."

Dean Miller, who is Miller's son and the co-producer of the album that's been in the works since 2015, says that when looking for singers to fill the roles of his late father and Price, he knew the three revered stars were the ideal choice.

"Ray is gone, and my dad is gone, so I thought, ‘Who else fits in that Mount Rushmore?’ Well, Merle and Kris. They were both very close to my dad, so I pursued both of them,” he shares via press release.

King of the Road: A Tribute to Roger Miller carries a bevy of country music stars, with Loretta Lynn, Dolly Parton and Alison Krauss, Eric Church, Kacey Musgraves and Ronnie Dunn all lending their voices to the far-reaching project that also features vocal performances by Ringo Starr, John Goodman, Cake, and Asleep at the Wheel and Huey Lewis.

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