That was pretty good.
I think Legend's voice did a superb job, the guy with his hands behind his back (the soccer looking guy) had a little too much fuzz on the microphone, and it sounded like he tried to shout some lines, but keeping quiet.
I would recommend you use photoshop to blurr certain frames, like when someone throws a punch, just for that added effect. Everything was pretty good, but the coloring and outline of the characters could've been more polished. It seemed like you used the brush for everything, you should try to use the pencil tool (hairline) to do everything, then just fill in with the bucket.