Metallica dedicated a song to embattled Green Day frontman Billie Joe Armstrong during their headlining set at the Voodoo Music + Arts Experience festival on Saturday after stepping in as last-minute replacements for the 21 Guns hitmakers.
Green Day were forced to pull out of the New Orleans, Louisiana event last month after Armstrong checked into rehab to address substance abuse issues following an onstage breakdown at the iHeart Radio Music Festival in Las Vegas.
Metallica were called in to fill the slot and they delivered a high-energy two hour set, opening with Hit the Lights and Master of Puppets.
Frontman James Hetfield joked about filling in for Green Day, shouting, "We! Are! Green Day! Except a little taller!" but he got serious later on in the show when he dedicated Battery to Armstrong, telling the crowd, "This one's for Billie."
During the encore, the band teased fans by playing the opening riff to Green Day's smash hit American Idiot, only for Hetfield to cut short the cover, stating, "We can't play that song."
He also gave Armstrong and his bandmates a boost of confidence, adding, "They're getting it sorted out, hopefully they get it fixed because the world needs them."
The 2012 Voodoo festival kicked off on Friday with Neil Young & Crazy Horse headlining the opening day, while Jack White is set to close out the three-day event by rocking City Park on Sunday night.