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MLS to Implement Concussion Substitutes Initiative

MLS clubs now have two more substitutes available for suspected concussions


NEW YORK (Monday, April 5, 2021) – Continuing its role as a leader in prioritizing player safety, Major League Soccer today announced that the league will participate in FIFA’s concussion substitute pilot program.

A concussion task force comprised of sporting and medical leaders from MLS, NWSL, U.S. Soccer, the USL, and NISA, have worked collaboratively to implement the initiative and have been approved by The IFAB and FIFA to participate in the trial.

Beginning in 2021, Major League Soccer teams will be allowed to make up to two concussion substitutes during a match to replace players suffering from a concussion or a suspected concussion, regardless of the number of substitutions already used. 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.

MLS teams will have the following three types of substitutions available each game:

  • Normal Substitutes: A continuation from 2020, each club has five normal substitutes available to make over three separate opportunities. throughout an MLS match. Any substitutions made during halftime, or between regulation and extra time, or between the two halves of extra time in the postseason will not count as one of the three opportunities.
  • Concussion Substitutes: Each team will be permitted to make up to two concussion substitutions only during instances of suspected concussions. A concussion substitution can be made immediately after a concussion occurs or is suspected, after an on-field assessment, and/or off-field assessment, or at any other time when a concussion occurs or is suspected. This includes when a player has previously been assessed and has returned to the field of play.
  • Additional Substitutes: If a team uses a concussion substitution, the opposing team will receive an additional substitution that will be available to use only after all five of its normal substitutions have been made. If a team makes a second concussion substitution, the opponent receives another additional substitution opportunity.

Each club’s technical staff will be responsible for designating the substitution type by providing the Fourth Official with the appropriate color substitution card: white for a normal substitution, pink for a concussion substitute, and blue for an additional substitute.

While referees may stop play due to a suspected head injury, the match officials will not be a part of the decision-making process to determine whether a player should or should not be replaced, nor will they determine if a normal substitute or a concussion substitute should be used.

Medical professionals in the facility, including team athletic trainers, team doctors and the Venue Medical Director, will continue to follow policies and protocols established by the MLS Concussion Committee for on-field and off-field assessment and management.

MLS will also continue to utilize the medical spotter program through which trained professionals monitor the match broadcast to identify potential head injuries and possible concussions. Those medical spotters are able to quickly provide video to the Venue Medical Director at the fourth officials table to assist in assessing head injuries and possible concussions.

The IFAB has set an initial 20-month trial period to test the concussion substitutes initiative in competitions around the world through Aug. 31, 2022. During its Annual General Meeting in March 2022, The IFAB will decide whether to extend the trial period or whether to make a decision on implementing concussion substitutes into the Laws of the Game.

Additional information on The IFAB’s concussion substitutes trials can be found here.

Major League Soccer will kick off the 2021 regular season on Friday, April 16.