Outside of, say, Led Zeppelin reuniting and then bringing Bob Dylan to the stage for a song, it’s honestly not possible to imagine a rock-star duet with this level of wattage. Last night, during a Rolling Stones show in Lisbon, Bruce Springsteen gorilla-walked onstage to join the band for a spirited rendition of “Tumblin’ Dice.” The Boss had previously joined the Stones onstage in New Jersey a couple of years ago, but you presumably half-expect Springsteen to show up anytime any band plays in New Jersey. I can’t imagine anyone saw this Portugal appearance coming. Check out fan-made video of the performance below.

There’s probably a book to be written about the contrast in stage presences between Mick Jagger and Bruce Springsteen. It’s like watching a peacock and a bulldog.