Jack White and Pearl Jam joined forces Saturday night for Portugal's NOS Alive, closing out the band's set with "Rockin' in the Free World."

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Early in the encore, Pearl Jam teased White's appearance by playing the riff to "Seven Nation Army" during "Porch."

You can check out the fan-shot footage of White joining the band on stage for "Rockin' in the Free World" below:

White previously joined Pearl Jam in 2016 for a performance of "Off the Earth' during a surprise concert at White's Third Man Records.

What do you think of Jack White's appearance with Pearl Jam? Let us know in the comments below!

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