Metallica paid tribute to Green Day at the Voodoo Music Exepriencein New Orleans on Saturday (October 27).

The rock band stepped in to Green Day's slot after Billie Joe Armstrong checked in rehab for substance abuse, forcing Green Day to cancel a series of appearances. But Green Day wasn't forgotten at the annual music festival.

During Metallica's two-hour set, James Hetfield told the crowd, "We're Green Day, just a little taller." According to Loudmouth.com, Hetfield later mentioned Green Day again, saying, "They're getting it sorted out, hopefully they get it fixed because the world needs them." After that, Metallica played a riff from Green Day's "American Idiot."

Metallica also dedicated the Master of Puppets track, "Battery," to Armstrong, telling the audience, "This one's for Billie."

• Nearly 100 acts played the Voodoo festival this year, including Neil Young & Crazy Horse, Coheed & Cambria and Jack White.
• Metallica guitarist Kirk Hammett recently told Billboard that the band will start working on a new album soon.
• On Decemeber 10, Metallica will release a live DVD called Quebec Magnetic.