In making an accurate offside decision, the alignment of the Assistant Referee with the second-to-last defender at the time the ball is played forward is a first key step. Following this step it is crucial that the Assistant Referee maintain concentration using a wide view across the field, tracking the closest to the farthest defender, one or more attackers, and their positions relative to each other.
Often, the location of the ball will only be within the AR’s peripheral vision at the time it is played forward. As the speed of the game increases, it becomes more important for the Assistant Referee to simultaneously take in three elements: 1) the location of the second-to-last defender, 2) the location of attackers positioned both onside and offside in relation to this defender, and 3) the exact time the ball is kicked. Turning the head completely or fully focusing on only one of the three elements, particularly the ball, must be minimized to reduce errors. Focusing on the ball, even for a short time, will cause the AR to miss the subsequent movements of the attackers and defenders.
In the clip from the July 21 game between FC Gold Pride and Boston Breakers, the Assistant Referee appears in good position with the second-to-last-defender (STLD). The defenders are staggered, and the near defender is beaten by the attacker’s run. At the time the ball is kicked, the attacker is at least even with the two far defenders. It appears that prior to the ball being kicked, the AR takes focus off the STLD and redirects it towards the player kicking the ball. By the time focus is returned after the ball is played, the attacker has moved beyond the near defender and appears to be offside when the ball is received, prompting the flag to be raised in error. It is crucial that the primary focus of the AR’s concentration remain with the STLD and that peripheral vision is used to register the ball being played forward.
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