LEAVING THE FIELD AT A RESTART

Question:
On a corner kick, player A places ball in the arc. Player B runs out of play and around the goal to the resume position on the back post. Opposing team had players on the post. Corner is crossed in by Player A and scored by Player B who ran out of play. Should Player B be allowed to return to the field since he deliberately ran off the field? Should Player B wait to be signaled back on by the official after the corner was played in? Shouldn’t this be a yellow card?

USSF answer (July 15, 2011):
The Advice to Referees tells us:

3.9 LEAVING THE FIELD IN THE COURSE OF PLAY
Players are normally expected to remain on the field while the ball is in play, leaving only to retrieve a ball or when ordered off by the referee. If a player accidentally passes over one of the boundary lines of the field of play or if a player in possession of or contesting for the ball passes over the touch line or the goal line without the ball to beat an opponent, he or she is not considered to have left the field of play without the permission of the referee. This player does not need the referee’s permission to return to the field.

If the player ran out of the field after the ball was placed and before the kick was taken _and returned only while the ball was in the air_, that player has left the field of play without the referee’s permission. Blow the whistle, cancel the goal, caution the errant player for leaving the field without permission, and restart with an indirect free kick for the defending team from the place where the ball was when play was stopped.