Considered part of the outlaw country genre, supergroup the Highwaymen brought together the GRAMMY-winning talents of Johnny Cash, Waylon Jennings, Kris Kristofferson, and Willie Nelson.

In 2014 Kristofferson and Nelson teamed with Merle Haggard on the 56th GRAMMY Awards for a Highwaymen-themed medley. Relative newcomer Blake Shelton also joined in on the fun.

Stars including Beyoncé and Steven Tyler swayed in the audience as Shelton sang and played along on "Highwayman," "Mammas Don't Let Your Babies Grow Up to Be Cowboys" and the Haggard classic "Okie From Muskogee."

"He's the big dog right now," said Haggard in 2014 regarding their new sideman.

"My manager called me and he said … 'From what I can tell, they pretty much want you to be one of the Highwaymen,'" Shelton remembers. "To be up there with Merle — who now we've lost — Kristofferson and Willie … I will never forget this."

Watch Shelton and more artists reminisce about the most memorable performances in GRAMMY history on the upcoming TV special "GRAMMYs Greatest Stories: A 60th Anniversary Special," airing Friday, Nov. 24 from 9–11 p.m. ET/PT on CBS.

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