AFL announces concussion rule change THE AFL has announced a rule change allowing the use of a team's substitute player as a temporary interchange while a player is being assessed for concussion. The rule change allowing the sub to be a temporary interchange for up to 20 minutes came as the AFL also revealed updated guidelines for the management of concussion in the sport. AFL medical commissioner Dr Peter Harcourt said key features of the updated guidelines included: Any player with a medically diagnosed concussion will not be allowed to return to play on the day of injury Sideline video review by team doctors of the relevant on-field incident as a part of the clinical assessment will be used at all major AFL venues The extensive SCAT3 assessment to determine whether a player is fit to return to play cannot take place for a minimum of 10 minutes after the on-field incident A player with any neurological symptoms or signs, video features of concussion and/or any evidence of a disturbance of mental state or cognitive function following trauma, can be considered to have concussion and must not return to play Where there is any suspicion of concussion, the player requires further evaluation including video footage review and assessment of symptoms, orientation, balance and cognitive function (SCAT3) prior to a final determination If a player is cleared of a concussion following assessment, they can be allowed to return to play, but should be monitored for the duration of the game as concussion symptoms are dynamic and can evolve over time Club medical officers may be required to provide full documentation of clinical assessments of concussion to the AFL medical directors for review. Full documentation will also be collected as part of ongoing research activities.