Over the weekend, Metallica headlined the 2012 Voodoo Music + Arts Experience in New Orleans after original headliners Green Day were forced to back out. Due to Billie Joe Armstrong's recent trip to rehab, Metallica stepped in on short notice, but took a moment to pay tribute to their friends in Green Day by performing a part of 'American Idiot' onstage (as seen in the video below).

During Metallica's two-hour set, frontman James Hetfield addressed the crowd. "We're Green Day, just a little taller," joked Hetfield. "They're getting it sorted out, hopefully they get it fixed because the world needs them." After paying tribute to the band, Hetfield and drummer Lars Ulrich played the intro and first verse of Green Day's 'American Idiot,' letting the audience sing loudly back at them as they played festival karaoke.

Metallica's Kirk Hammett recently spoke with Fuse about filling in Green Day's spot. "We got a message about [in early October] asking us if we're able to fill in for Green Day, because Billie Joe was having some issues," said Hammett. "We discussed it between the four of us and we all said, 'Yeah, it would be great thing for us to do and it would also be great to help out Billie Joe, 'cause he's a friend of ours and we love Green Day. If we can help them out in any way possible, we're always happy to do it, 'cause we love those guys. It's actually an honor for us that they approached us and asked if we can fill in."

Check out our full coverage of Metallica's performance at the 2012 Voodoo Music + Arts Experience and watch the band play 'American Idiot' in the video below.

Metallica Play Green Day's 'American Idiot' Live at Voodoo Music + Arts Experience

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