Teams progressing to the latter stages of the FA Cup next season will be allowed to field a fourth substitute in extra time, the English Football Association (FA) announced on Wednesday.
The International Football Association Board (IFAB), the game's law-making body, is carrying out a global study into a proposal for teams to make a fourth replacement during extra time.
The FA said as a trial for the study it would introduce the innovation for the quarter finals, semi-finals and final of the FA Cup, subject to IFAB approval.
If the FA gets the go-ahead from the IFAB, clubs that have used three substitutes from the seven players named on their bench during the tournament's final three rounds will be allowed to introduce a fourth player in extra time.
The format was first used in this year's Copa America.
"With the cup now adopting a straight knockout format from the quarter-finals onwards, the introduction of a fourth substitute in extra time will bring extra intrigue and interest," FA chief executive Martin Glenn told the governing body's website.
"Also, from a technical point of view, it will be interesting to see how managers use the chance to make an additional substitution in such high-profile games and the impact it has on the final result.
"Player welfare and being mindful of the number of games people play at the elite level has also been a consideration."
The FA Cup begins on Aug. 5, with the final at Wembley in May 2017.
