If Nick Diaz fails to beat Georges St. Pierre for the UFC welterweight title on Saturday night, it won't be because he wasn't well conditioned. Just check out what he was able to do to this poor speed bag. It's hard enough to sit through this entire clip, let alone actually throw the punches necessary to do what Diaz did here.
RELATED: The 50 Most Brutal Knockouts in MMA History (Video)
[via Caged Insider]