In this Headbanger Region matchup for Round 2 of March Metal Madness 2014, two heavyweight discs battle it out to advance to the next step in being named the greatest 21st century metal album so far. In this battle, we have two bands that are true masters of the riff and pumping unrelenting power into the veins of listeners.

Pantera advanced into Round 2 of the Headbanger Region by beating out Shadows Fall's breakout record, 'The Art of Balance.' The sole 2000s Pantera release, 'Reinventing the Steel,' moves on in March Metal Madness, powered by monster tracks such as 'Goddamn Electric' and 'Revolution Is My Name.'

Mastodon beat out fellow Georgian powerhouse Baroness in Round 1 of our tournament, but now, Mastodon's 'Leviathan' faces perhaps the greatest Southern metal band in history. Mastodon wield a phenomenal weapon, however, with 'Leviathan,' which is widely considered one of the most important metal records unleashed in the 2000s.

Pantera's 'Reinventing the Steel' or Mastodon's 'Leviathan'? Vote for your favorite 21st century album in the poll below!

(This poll will end on Sunday, March 16 at 11:59 PM ET. Fans are able to vote once per hour, so keep coming back to make sure your favorite album wins!)