What action is taken by the assistant referee during a penalty kick?

During a penalty kick, the primary responsibility of the assistant referee is to monitor the actions of the goalkeeper to ensure compliance with the Laws of the Game. Specifically, they pay attention to whether the goalkeeper moves off the goal line before the penalty taker strikes the ball. This aspect is crucial because the Laws state that the goalkeeper must remain on the goal line until the ball is kicked. If the assistant referee observes any violation regarding the goalkeeper's positioning, they can alert the main referee, who may then decide to retake the penalty kick if necessary.

Other options do not pertain directly to the specific role and responsibilities assigned to the assistant referee during a penalty kick. For instance, indicating whether a goal is scored is a task for the referee, while calling offside is typically not applicable in this context since the play is stopped for the penalty. Additionally, ordering substitutions is not relevant during a penalty situation and falls within the referee's jurisdiction.