Concussions which occur but are not discovered put the player at risk for remaining in the game and possibly having another concussion which may be much more serious, since complete recovery from the first concussion had not occurred. This article demonstrates that KDT testing of every player after every sporting event in which a concussion could have occurred, can be an effective tool to determine a player’s removal from play and a resulting referral to the player’s doctor, even if the concussion was not witnessed during the game.