mmm maybe grass level is not at top, but it should be at least equally divided with my team and the opponent... instead injuries are all on one side... and I've my theory (that's why I thinking the code is bugged): in my tournament my team is far far better than other teams (except one) and in all matches I've Always 70-80% of the ball possess. I'm totally sure that injuries statistically happen to the team with the ball... and that is neither fair or realistic.
As I was vs the other good team or other good teams in the cup League... the injuries stopped.