On Saturday (July 7), the Roots joined Bruce Springsteen and the E Street Band onstage at the Roskilde Festival in Denmark for 'The E Street Shuffle.' Nearly 100,000 people witnessed the performance between the classic rockers and the hip-hop band.

Back in March, when Springsteen appeared on NBC's 'Late Night with Jimmy Fallon,' the two acts nailed a riotous version of the same song that ended with the studio audience dancing on the stage. In addition to being one of hip-hop's most acclaimed groups, the Roots are Fallon's house band.

Earlier in the day, the Roots performed at the festival. Springsteen watched from the wings, which caused drummer Questlove to tweet "Mind Blown" at the thought of the Boss watching him.

Joining Springsteen's 17-piece E Street band were Black Thought, F. Knuckles, Captain Kirk Douglas, James Poyser, Mark Kelley, Kamal Gray and Damon “Tuba Gooding Jr.” Bryson. Douglas was even given the opportunity to share the mic with Springsteen for the bridge.

Watch Bruce Springsteen, the E Street Band and the Roots perform 'The E Street Shuffle'