Talk about good timing! Just this last weekend during the Game of the Week training I was discussing with some referees the importance of the AR staying on top of the offside position. My argument was that you should always be focusing on that second to last defender (or the ball) and that if you have to ignore other things to be on top of offsides, then let them go. Even during my most abbreviated pregames I make sure to touch on the topic.
Well, apparently US Soccer agrees.
From the U.S. Soccer Communications Center:
Subject: Priority of Assistant Referee Responsibilities
In a recent professional exhibition match, a group of referees, instructors, and assessors was discussing an incident in which the assistant referee was faced with a conflict in priorities – whether to hang back and observe the goalkeeper with the ball in case the goalkeeper went outside the penalty area with the ball still in his hands (a handling offense) or to move up field to get in position for assisting with offside in case there was a quick counterattack after the goalkeeper released the ball. The conversation was vigorous, but the matter should have been easily settled by reviewing the relative importance of the two possible violations.
A similar conflict in priorities can arise when a team is attacking along the touchline and the assistant referee must choose between looking up the touch line to signal if the ball leaves the field and looking across the field to monitor whether an attacker moves into an offside position. Dividing attention this way is not impossible, but both responsibilities will suffer.
The single most important responsibility for the assistant referee is making timely and accurate offside decisions. All other duties outlined in Law 6 are secondary.
Offside decisions are often “game critical” regardless of their specific result. A decision for offside is just as likely to be challenged as a decision against an offside violation. Whether the issue is offside position or involvement in active play, if a goal is called back, allowed, or interrupted as a result, the decision will be controversial. It must therefore be supported by the best fitness, mechanics, communications, and concentration that the assistant referee can bring to bear.
If there is not much difference between where the assistant referee must focus to handle each different duty then clearly both duties should be attempted. As one duty increasingly becomes a distraction for the other, the assistant referee should attempt to adjust positioning to reduce the conflict. Where the distraction is too great, the only solution is to focus on offside, leaving to other members of the officiating team the responsibility of covering to the best of their abilities the less critical conflicting duty.
Among the topics which must be covered in the officiating team’s pregame discussion is the issue of what the assistant referee should do to resolve a conflict between offside and such other responsibilities as determining if the ball has left the field, which team has possession, and the occurrence of violations which do not involve violence.