UEFA has announced that clubs will be allowed to make a fourth substitution in next season's Champions League.
The rule will only apply in knockout games that have been pushed to extra time, meaning that an additional change can be made if three substitutions have already occurred during the match.
The European governing body has also decided to introduce new kickoff times for the 2018-19 competition, with some games getting underway at 8pm and two games on both Tuesday and Wednesday starting at 5.55pm.
In addition, once the group stage has been concluded, clubs will be allowed to add three new players to their squads without any restrictions.
This means that January signings will be permitted to join their new club's campaign.