Concussions are becoming an increasingly visible injury in soccer. In the U.S., efforts to reduce the frequency of concussions and ensure they are properly treated have been implemented from the youth to professional level. For example, the Major League Soccer concussion protocol calls for a player to be removed from the field and be immediately evaluated by a doctor for concussion symptoms.
Of course, the implementation of the protocol is imperfect and at times players who seem like they should be substituted due to a concussion continue playing. Partly this is due to the difficulty of making concussion diagnoses in a highly charged match atmosphere, but also because of the desire of players to stay in a game even if they are injured.