Jack White made a surprise appearance during Pearl Jam‘s headlining set at Portugal’s NOS Alive festival Saturday, joining the band on guitar.

During “Porch,” Pearl Jam seemed to pay tribute to White – who performed at NOS Alive prior to the band’s set – by weaving the iconic riff from White Stripes’ “Seven Nation Army” into the Ten song’s lengthy jam.

After the set’s penultimate song, Pearl Jam’s “Alive,” White joined Pearl Jam onstage for their frequent closer, a rendition of Neil Young’s “Rockin’ in the Free World,” with White delivering multiple solos to close out the headlining set.

The surprise White cameo marked the first time he performed alongside Pearl Jam since the band played a secret Third Man Nashville gig in 2016, which featured White’s guesting on the then-unreleased song “Of the Earth.” White later released the pre-Bonnaroo gig, recorded in front of 250 fans, as one of his Third Man Vault packages.

Pearl Jam will perform July 17th at London’s O2 Arena before returning stateside next month for their Seattle “Home Shows” followed by a brief “Away Shows” stadium tour.