A CONCUSSION sub will be introduced into the AFL this season after the AFL Commission approved the change on Monday.

The rule change will allow teams to use its substitute as an interchange player for a 20-minute period while a concussion assessment is taking place.

Under the new guidelines the SCAT3 assessment (a tool used to determine whether or not a player is suffering concussion) will not begin until a minimum of 10 minutes has elapsed following the on-field incident.

Club doctors will review video footage as well as orientation, balance and cognitive function as part of their assessment.

It is considered a key change to support the intent of conservative new concussion guidelines that will be introduced this season.

The rule change will ease pressure on doctors as they make assessments and is consistent with the recommendations from the Consensus Statement of Concussion released last Tuesday.

That statement, which arose from the International Conference on Concussion in November, said sports should consider rule changes to ensure the assessment of players suspected of suffering head knocks can occur "without affecting the flow of the game or unduly penalising the injured player’s team".

The AFL Medical Officers Association recommended the rule change and it had club support.