Cabral said:Just a little bit from what martial arts training I've had, a tumble to regain your feet without provoking an attack of opportunity would not be the rock back and hop to your feet, it would be a roll backwards over one shoulder.
And in real martial arts, your attacker would still move forward and kick you in the face as you are trying to get your feet under you after your roll.

Most martial artists (except those who practice Brazilian Jiu-Jitsu or some other form of grappling) are in serious trouble when they get on the ground.