Power output imbalance

Thanks for the great advice! I agree with everything I’ve just read. Now for another question. Does ROM difficiency because of lack of strength (ex. Hip flexor) classify as ROM restoration, or do you mean only flexibility? Also, once he’s cleared, is it a good idea for him to starting kicking immediately by slowly progressing the number of kicks, or should we keep him away from the ball for a few more weeks/ months. Before the initial injury, he ran like he was kicking a ball (a lot of backside, little heel flick, little knee lift). I don’t want him to pick up those habits again, but I’m not sure if him kicking the soccer will make it easier to do so.