There was 12 on the field, but the 12th was standing next to the official who was doing the subs. At no point was she ever involved in the play. He made sure that she stayed right next to him. He attempted to signal the main official but he was never acknowledged. When it was apparent that the main official was not going to acknowledge the sub she was backed off the field. At no point was she involved in any play, contact the ball, or marked by a CSU player. Since the corner kick was on the opposite side of the field the CSU players probably did not even see her.