Brothers Osborne made a surprise appearance with rockers Foo Fighters onstage in Edmonton, Alberta Monday night (Oct. 22), treating the crowd to a rendition of Tom Petty & the Heartbreakers' 1977 classic “Breakdown.”

Foos frontman Dave Grohl called the duo to the stage with glowing words: "There’s a wonderful band that played here," he noted, referring to the Brothers' Oct. 21 show at the Shaw Conference Centre. “They were drinking with us before the show, so I feel obligated to give them a little something-something.”

The cover of the slinky-smooth single, which paid tribute to what would be the late Petty's 68th birthday on Oct. 20, featured John Osborne ripping it up on guitar while brother T.J. traded vocals with Grohl.

The crowd weren't the only ones excited by the inspired pairing. The duo themselves posted a succinct "Holy s--t" on Instagram following the show. We'd have to agree that's a good way to sum it all up!

Although Foo Fighters are undeniably in the rock genre, their guitarist Chris Shiflett is a well-seasoned country fan, having released his own album in the genre (West Coast Town) last year. He also mans a podcast dedicated to country and Americana music, Walking the Floor, on which he's hosted the Brothers Osborne as guests.

The duo launched their headlining tour in late August. It's set to run through the beginning of December and includes openers Lucie Silvas and the Wild Feathers.

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