In what situation can soccer teams make an extra substitution?

Club León booked their place in Liga MX’s Apertura 2023 playoffs thanks to a nervy home victory over Santos Laguna, which sets up a liguilla quarter-final clash away to favourite Club América. Los Panzas Verdes looked to be cruising to victory after going 3-0 but ended up hanging on as Los Guerreros mounted a fightback in the final quarter of the game. During those closing stages, the hosts raised a few eyebrows by making a sixth substitution, one more than is normally permitted.

Why were León allowed to make six substitutions instead of five?

In the vast majority of elite-level competitions, teams are allowed to make five changes under “normal” circumstances, a number which first increased from three during the covid-19 pandemic. Absences caused by the virus, along with fixture schedule demands and player fatigue, were citied as reasons for the modification.

At Estadio León on Sunday, Nicolás Larcamón had already made four substitutions but sent both Stiven Barreiro and David Ramírez on for Lucas Romero and Omar Fernández in injury time. The Argentine midfielder was carted off the field wearing a neck brace after accidentally being kicked in the jaw by Harold Preciado.

Because Romero had suffered a head injury, León implemented the concussion protocol used by Liga MX which allows teams to use an extra substitute to replace a player that is suspected to have suffered a concussion.

What concussion protocols exist?

Two protocols were created by IFAB (the International Football Association Board), who determine the laws of the game. Protocol A allows teams to use a maximum of one concussion substitute in a match, with the opposing team not permitted to also make an extra change. Club doctors are given a maximum of three minutes to determine whether they believe a player has suffered a concussion.

Protocol B enables the affected team to make a maximum of two concussion substitutions. This time, the opposing team is allowed to make the same number of changes at the same time, regardless of the reason.

Different rules in FIFA World Cup and UEFA Champions League

Different competitions use different protocols, while others use neither. Protocol A is used in the FIFA World Cup and was deployed in the final between Argentina and France. Adrien Rabiot was the man forced off the field and the French were ultimately allowed to make seven substitutions because the match went to extra-time, which already afforded both teams the chance to make an additional change.

The UEFA Champions League, on the other hand, doesn’t permit concussion substitutions, as is the case for every UEFA-organised competition.