I can't remember if it was our game or Ga-Oak, but the announcers mention that if the RB was even with the QB, then it would be a pass. If the RB was a yard or 2 deeper than the QB, then the play would be a run. I remember watching this key and it was true on over 75% of the plays that I saw. If the announcers could see this, then a DC would see it also. Again, I can't remember which game is was, but I only watched those 2 yesterday.