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Watch Chris Stapleton, Sturgill Simpson's Furious Guitar Duel on 'SNL'

Simpson, a surprise guest, joined his fellow Kentucky native on Stapleton's "Midnight Train to Memphis'"and "Hard Livin'"

Sturgill Simpson joined Chris Stapleton for two fiery performances on 'SNL.'

Chris Stapleton and Sturgill Simpson – two of country music's most vital artists – performed onstage for the first-ever time on Saturday night. Stapleton was the scheduled musical act on Saturday Night Live, hosted by Will Ferrell, but a few hours prior to the broadcast he tweeted that he'd be joined by a special guest, bringing some "extra Kentucky in NYC." Both singers hail from the Bluegrass State.

Together, the singer-guitarists made for a potent pair, delivering furious versions of "Midnight Train to Memphis" and "Hard Livin'," two tracks off Stapleton's latest album, From A Room: Volume 2. Simpson, ever the rogue, grinned like the cat who ate the canary as he laid down squealing guitar solos and fills on both songs. Occasionally, Stapleton matched him, making for an incendiary Telecaster duel.

Turning both songs into duets, Stapleton and Simpson's unique vocal styles were surprisingly complementary: Stapleton the bluesy howler, Simpson the consonant-swallowing drawler. "Hard Livin'," in particular, illustrated their vocal chemistry, with Stapleton's bellowing "I was known to have a good time" setting up Simpson's deep-throated response, "But I never could walk the line."

Stapleton first performed on Saturday Night Live in January 2016, while, last year, Simpson made a memorable, guitar-smashing SNL debut.

Stapleton is nominated for three trophies at Sunday night's 60th annual Grammy Awards, including Best Country Album for From A Room: Volume 1. Simpson's A Sailor's Guide to Earth won that category last year. Stapleton will also perform with Emmylou Harris during the telecast in one of the show's signature "Grammy moments." Though fans of Stapleton and Simpson might argue they already witnessed one on Saturday night.