For what it is, it's pretty good.
As far as totally random sprite fighting goes, this is pretty good. Appropriate music, smooth action, and very flashy effects make this easy on the eyes.
However, there is nothing interesting about this flash aside from random eye candy. The opening where the guy opens up the program and has to leave suddenly to answer his phone is a waste of time, and considering there is no plot aside from two characters fighting just because it would have been better if you had just jumped right into the action. It's further accented by the fact that the character make no use of the environment, so them popping out the screen and fighting on the desk doesn't offer anything different than if they'd just be in a pixilated background.
Secondly while most of the fight was smooth the random intervals where the muay thai fighter poses while groupies cheer around him just didn't make sense. I don't know if it's relevant in the game itself but all it did was break up the action.
Lastly, there was nothing really exciting about this fight. Neither character showed any sign of taking any damage from an attack, there was nothing at stake in their battle, and they threw out flashy attacks so haphazardly that it felt more like watching a dance than actual combat. Combat should be visceral, and attacks should do more than just knock a guy on his back so he can get up immediately.
There is talent in your work, now just work on making it worth watching.