Pearl Jam played a nearly three-hour set at the New Orleans Jazz & Heritage Festival on Saturday night (April 23), and even though that's nothing for the legendary rockers, they got an assist from some of their rock 'n roll pals.

Red Hot Chili Peppers guitarist Josh Klinghoffer and drummer Chad Smith and Kings of Leon drummer Nathan Followill hopped onstage with Eddie Vedder and co. to perform a cover of Neil Young's "Rockin’ in the Free World," and it was a match made in rock heaven.

New Orleans Jazz Fest saw a slew of performers this weekend, with one more batch to go. Next weekend, Neil Young himself will come out, along with a variety of artists like Beck, Snoop Dogg and Mavis Staples.