Blood and Bone
Michael Jai White is such a badass in this. This is the story of an ex-con, who's also an expert martial artist, who engages in underground fighting so that he can fulfill his pledge to a dear friend. Basically, it's a modern day Lionheart. The martial arts choreography was great, and the fight scenes were a lot of fun, which is pretty much the entire point. There really isn't much more to the movie, good or bad.
Here's the very first(short) fight scene so that you can get a taste
of the badassery. Don't worry, it doesn't spoil anything.