NEW YORK (August 17, 2017) – Major League Soccer today announced that a fourth substitute will be available to teams during the Audi 2017 MLS Cup Playoffs and 2017 MLS Cup for postseason matches that require the two, 15-minute extra time periods.
In addition, an update to the MLS Disciplinary Committee parameters has been introduced for incidents involving Video Review.
The International Football Association Board (The IFAB), which oversees changes to the Laws of the Game, has approved experiments with a fourth substitution during extra time. Under the IFAB parameters, a fourth substitute may only be used if a game goes to extra time and may be used regardless of the number of substitutes a team made during regulation time.