Those in charge of football's rules and laws will allow teams to replace players with head injuries as early as January 2021
Premier League clubs have agreed "in principle" to introduce additional permanent concussion substitutions but the number of regulation in-game changes allowed has not been increased.
Football's lawmakers, the International Football Association Board (IFAB), on Wednesday announced planned trials for concussion substitutions were approved after "less than a year of detailed consultation with relevant stakeholders, medical concussion experts, team doctors, player representatives, coaches, competition organisers, refereeing and Laws of the Game experts".
Under the proposed protocols, players with an actual or suspected concussion will be "permanently removed from the match to protect their welfare", with the team allowed to bring on a replacement.