It's been a long time since we've heard a proper new Metallica song, but that'll change when the band hits South America for a series of March tour dates.

As we previously reported, the band is playing all-request shows during its upcoming tour, with a twist: one slot in the 18-song set list is being reserved for a new song. And as proof that they're actually writing again, the group posted a photo to its Facebook page on March 13 with a caption reading "Working out the kinks in the new song that we'll be debuting in South America in a couple days."

Metallica collaborated with Lou Reed for the 'Lulu' LP in 2011, but the band's last full-length standalone effort was 'Death Magnetic,' released in 2008. In an interview earlier this year, guitarist Kirk Hammett explained the delay by saying, "We've been procrastinating greatly ... We’ve pretty much come up with every sort of excuse we can not to start work on the album, but we’ve run out of excuses, so we pretty much have to start work on it now."

The band is due to kick off its South American tour on March 16 in Bogota, so we should start seeing YouTube clips of the new song pop up shortly.

Metallica 2014 South American Tour Dates
3/16 - Bogota, Colombia
3/18 - Quito, Ecuador
3/20 - Lima, Peru
3/22 - Sao Paulo, Brazil
3/24 - Asuncion, Paraguay
3/27 - Santiago, Chile
3/29 - Buenos Aires, Argentina
3/30 - Buenos Aires, Argentina