The annual Americana Music Festival is always full of (sometimes not-well-kept) surprises, but one of the biggest of 2019 was Keith Urban's guest appearance during Foy Vance's showcase. The country superstar joined the Northern Irish singer-songwriter onstage at Nashville's Cannery Ballroom on Friday night (Sept. 13), to perform Vance's song "Burden."

“I didn’t know I needed this guy in my life until I met him. And now that I met him, I can’t f--kin’ do without him," Vance told the crowd before bringing Urban up onstage. The pair's performance of "Burden" became a seven-minute jam, including plenty of musical flourishes from Vance on piano and Urban on guitar. Readers can press play above to watch.

Originally from Vance's 2016 album The Wild Swan, "Burden" is a song that Urban recorded and released himself earlier this year, after performing it at the 2019 ACM Awards. Urban felt an immediate connection to the track, because he's been on both sides of the equation: He and his wife, actor Nicole Kidman, have supported each other -- just like any strong couple -- through life's ups and downs. When Kidman's father died in 2014, it was Urban's turn to be the strong one; earlier on in their marriage, Kidman's strength helped him in his journey to sobriety.

Vance was backed throughout his AmericanaFest set by "a fine-ass band," in Urban's words, the majority of which was female musicians and singers. Singer-songwriter Bonnie Bishop, who performed before Vance, sang harmonies during the show.

Vance recently released two new album, From Muscle Shoals and To Memphis, each recorded in the legendary musical city with which it shares its name. Urban, meanwhile, has a new single, "We Were," out now, and is recording more new music.

The 2019 Americana Music Festival runs through Sunday (Sept. 15). The week-long event features panels, parties and performances throughout Nashville. More than 300 acts are playing the event, which also includes the annual Americana Honors & Awards ceremony.

WATCH: Devin Dawson Covers Foy Vance's "She Burns"

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