in play. Marks may optionally be made on the goal line and touchline at a distance of 10 yards from the corner area to assist the referee in enforcing this provision. The ball is in play when it is kicked and clearly moves; it does not need to leave the corner area. The player taking the corner kick may not touch the ball a second time before it has touched another player. The attacking side may score directly from a corner kick, though this is uncommon. An own goal may not be scored directly: in the extremely unlikely event of the ball going directly into the attacking team's own goal from a corner kick, a corner kick would be awarded to the opposing side. An attacking player who directly receives the ball from a corner kick cannot be penalised for offside. Infringements If the kick is taken with a moving ball, or from the wrong place, the corner kick is retaken. Opposing players must retire the required distance as stated above. Failure to do so promptly may constitute misconduct and be punished by a yellow card. A player who excessively delays the restart of play is cautioned. It is an offence for the kicker to touch the ball a second time before it has been touched by another player; this is punishable by an indirect free kick to the defending team from where the offence occurred, unless the second touch was also a more serious handling offence, in which case a direct free kick is awarded to the defending team. Tactics in taking and defending a corner A common tactic is for several attackers to stand close in front of the goal, whereupon the corner taker crosses the ball for them to head into the goal. The defending team may choose to form a wall of players in an attempt to force the ball to be played to an area which is more easily defended. However, this is not done often because defending players must remain at least 10 yards from the ball until it is in play. The defending team also has the choice of whether to instruct a player to adopt a position beside one or both of the goalposts to provide protection to the goal in addition to the goalkeeper. The thinking behind placing a player beside a goalpost is that it means more of the goal