Watch Jason Isbell Pay Tribute to Warren Zevon on 'Letterman'

Americana A-lister plays 'Mutineer' with help from Amanda Shires, Mickey Raphael

With a new, "celebratory" album hitting stores in July and a baby due by early fall, there's about to be a lot of noise in Jason Isbell's life. Maybe that's why he chose to dial things back for his performance on the Late Show With Dave Letterman Friday night, hitting the Ed Sullivan Theater's stage with just an acoustic guitar and a two-piece band.

The song? A stripped-down version of Warren Zevon's "Mutineer," one of the two cover tunes from Isbell's new EP, Sea Songs

Zevon, a frequent musical guest on Letterman's program during his lifetime, had performed the song himself during a Late Show appearance on October 30, 2002, less than a year before losing a battle with lung cancer. It was his final public appearance ever. More than a decade later, Isbell's performance helps bring the song full circle, hitting the airwaves during the final stages of another acclaimed career: David Letterman's tenure as the longest-running late-night host in TV history.

In the performance, Isbell trades harmonies and sideways glances with wife Amanda Shires, while Willie Nelson's harmonica wiz kid, Mickey Raphael, sweeps in and out of the mix. It's a tender, toned-down performance, one that emphasizes the punch of Zevon's lyrics and the connection between two of Americana's biggest sweethearts rather than the usual swagger of Isbell's backup band, the 400 Unit. When the song concludes, a genuinely moved Letterman, whose last Late Show episode is less than a month away, says, "Jason, I can't thank you enough for everything. You've been great to us. Thank you."

Something More Than Free, Isbell's fifth album since leaving the Drive-By Truckers, is due out July 17th.