Foo Fighters stunned the audience with a surprise onstage appearance from the easy listening icon and traditional pop singer Michael Bublé when the Dave Grohl-led rockers played San Francisco's Outside Lands Music Festival 2023 over the weekend.

The unlikely live collaboration consummated a joke that Grohl has employed at Foo Fighters' latest shows, as EW reported: The Foos regularly invite an audience member to sing Bublé's 2009 hit "Haven't Met You Yet" as part of a cover song medley. But Grohl has quipped that those who volunteer don't know all the words to the Bublé tune. Do you?

Watch the video near the bottom of this post.

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Speaking to the Outside Lands crowd amid Foos' Aug. 12 set, Grohl said, "At the last couple shows, I always look out and someone's like, 'I know the Bublé song. I'll come up and sing it.'"

However, "Every time someone says they know this song, they don't know the fucking song," the Foo Fighters bandleader added.

The Bublé-assisted performance followed a medley that included covers of the Beastie Boys' "Sabotage," Devo's "Whip It" and Nine Inch Nails' "March of the Pigs." The medley is a nod to other artists that current Foos drummer Josh Freese has played with.

But when Grohl went to invite a fan onstage, Bublé himself was reportedly in the crowd holding an I heart Bublé sign. "Hold on, we got a super fan — he's got the 'I love Bublé!" Grohl observed.

"This motherfucker better know the song," the Foo Fighters leader added early in the onstage collab before jokingly reacting, "Oh my god, it's Michael Bublé!"

Grohl then offered more context. "I'm just gonna tell you something, and I'll make it fucking quick because we don't have a lot of time," Grohl said. "For real — we've been doing that thing where people from the audience come up and say, 'I know the fucking song,' and they walk up, and they're like, 'I know the first verse.' They don't know it!"

Pointing to Bublé, he explained, "So this badass motherfucker — and I'm not even kidding — flew in today from Argentina to fucking sing that song to you guys. Because there's no such thing as taking a joke too far."

See Foos' upcoming tour dates under the clip.

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Foo Fighters' Live Medley Featuring Michael Bublé - Aug. 12, 2023

Foo Fighters 2023 Tour Dates

Sept. 3 – Aspen, Colo. @ Jazz Aspen
Sept. 7 – Curitiba, Brazil @ Couto Pereira
Sept. 9 – Sao Paulo, Brazil @ The Town
Sept. 15 – Chicago, Ill. @ Riot Fest
Sept. 17 – Asbury Park, N.J. @ SeaHearNow
Sept. 19 – Virginia Beach, Va. @ Veterans Amp.
Sept. 21 - Louisville, Ky. @ Louder Than Life
Sept. 23 – Las Vegas, Nev. @ iHeart Festival
Oct. 1 - Dana Point, Calif. @ Ohana Festival
Oct. 3 – Phoenix, Ariz. @ Talking Stick
Oct. 5 – El Paso, Texas @ Haskins Ctr
Oct. 7 – Austin, Texas @ ACL
Oct. 14 – Austin, Texas @ ACL
Nov. 26 – Abu Dhabi, UAE @ Grand Prix
Nov. 29 – Perth, Australia @ HBF Park
Dec. 2 – Adelaide, Australia @ Coopers Stad.
Dec. 4 – Melbourne, Australia @ AAMI Park
Dec. 6 – Melbourne, Australia @ AAMI Park
Dec. 9 – Sydney, Australia @ Accor Stad.
Dec. 12 – Brisbane, Australia @ Suncorp Stad.

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