Luke Bryan and Dierks Bentley took some time out from getting ready for the ACM Awards to stop by The Late Show With Stephen Colbert for a very special performance. The country stars joined together for a one-of-a-kind cover of the Merle Haggard classic, "Ramblin' Fever."

Bryan and Bentley teamed with Jon Batiste & Stay Human for the performance, with Bryan kicking it off by singing the classic opening lines: "My hat don't hang on the same nail too long / My ears can't stand to hear the same old song."

Bentley and Bryan trade lead parts throughout the song, but join together in harmonies for the choruses, with Bentley showing off a different part of his voice than usual by singing the high harmonies above his friend and ACM co-host.

The band adds piano, sax and even some tuba accompaniment to a truly unique interpretation of the country classic, which was the title song to Haggard's 1977 Ramblin' Fever album. Released as the album's second single, it reached No. 2 on Billboard's Hot Country Singles & Tracks chart.

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Bentley is also part of the all-star lineup for the upcoming Merle Haggard tribute concert Sing Me Back Home: The Music of Merle Haggard. That show will take place at the Bridgestone Arena in Nashville on April 6, 2017, which would have been Haggard’s 80th birthday.

Bentley and Bryan are returning to co-host the ACM Awards for the second time in 2017, and the good friends have a plan in place if they make any errors in announcing the awards, as happened at the Oscars.

"Luke’s going to have a wardrobe malfunction. At least that way everyone talks about that and not the show," Bentley joked to the Tennessean recently.

"That’s our approach, Dierks — train wreck the show," Bryan added.

The 2017 ACM Awards air live from Las Vegas on Sunday, (April 2) at 8PM ET on CBS.

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