What is the AR-Referee procedure?

AR observes an attacker impedes the progress of the the goalkeeper. This prevents the goalkeeper from moving into position to stop the ball from entering the goal. What is the AR’s procedure in this situation to communicate to the Referee that the goal should not be allowed.

2nd part. What is the AR procedure if it is the goal scorer who commits a foul (like intentionally handling the ball into the goal)?

USSF answer (January 18, 2011):
First, before considering signaling for any possible offense, the AR should be certain that the referee could not see the action in question. If that is not a factor, then the AR should follow the instructions regarding a goal to be disallowed, as given on p. 27 of the USSF publication “Guide to Procedures for Referees, Assistant Referees and Fourth Officials” for specific situations, including the situations you asked about:
– If the scorer was offside at the moment the ball was passed to him or her, signals offside
– If there was a foul by an attacker, stands at attention with the flag held straight down at the side
– If a player other than the scorer was in an offside position and, in the opinion of the assistant referee, was interfering with play or with an opponent, stands at attention with the flag held straight down at the side
– Assumes the proper position for the restart indicated by the referee
• Is prepared to signal referee in accordance with pregame discussion if further information needs to be given to assist in making the correct decision

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