The purpose of this rule is to promote an competitive balance and ensure a positive playing environment in matches where a significant goal differential develops.
When a team falls behind by five (5) or more goals, that team may add one additional field player to the match. This adjustment remains in effect only while the goal differential is five or greater, and the leading team may not add players under this rule.
If the trailing team reduces the deficit to four (4) goals, the extra player must be removed at the next natural stoppage of play. Should the differential increase again to five or more, the trailing team may reintroduce the extra player.