Major League Soccer gives clubs the option of two additional substitutes during games in the 2021 regular season. Spearheaded by FIFA, the “concussion substitute pilot program” allows clubs two additional subs per team per match to replace players who get a concussion or a suspected concussion. FIFA and IFAB are participating in the trial program, which will run for the next 20 months until August 31, 2022.
According to the announcement, the subs may be used:
- immediately after a concussion occurs or is suspected;
- after an on-field assessment, and/or after an off-field assessment; or
- at any other time when a concussion occurs or is suspected (including when a player has previously been assessed and has returned to the field of play).
MLS is also keeping the five substitute rule that they implemented during the 2020 season, though they still must be made during a maximum of three opportunities during the game. Subs made during halftime or between regular and extra time do not count as one of the three opportunities.
Match officials may stop play due to a suspected head injury, but they will not be part of the decision-making process to determine whether or not a player should be replaced. That decision will be made by the medical professionals in the facility (including team athletic trainers, team doctors, and the medical director at the venue).
The announcement also stated that “providing clubs an additional two concussion substitutes allows teams to make substitutions in the interest of player health and safety, without being placed at a competitive disadvantage.”