foul or incidental contact

[kansassoccerref]

Soccer (especially American soccer) is a game of contact, some deliberate, some incidental. The art of refereeing soccer is to sort out what contact you're going to allow and what contact you'll whistle. A good rule of thumb is to consider the aftermath of the contact and ask yourself the question "Did the contact affect the flow of play?" If it does, you're probably going to want to call the foul (unless you choose to apply advantage). For instance, if a defender runs at an attacker slightly out of control and makes contact with the attacker, you would need to see how the attacker responds. If he/she keeps the ball at feet and continues to play, it may be best to allow the game to continue to flow. If the contact caused an interruption in the attacker's ability to play the ball (such as a slight stagger that takes away momentum), a foul would be appropriate.

A couple of other factors to consider are the age of the players involved and the general tone of the game. You can give older players a little more leeway, giving them a chance to play through the contact and allow flow of play to continue. Usually younger players should have the fouls called, since it helps them learn what is foul contact (and it helps keep the parents' sideline screaming down a bit too!). If the game is getting quite physical, the referee may want to call the game a bit tighter to maintain match control. The key thing is to be sensitive to the players' reactions -- that will tell you what they will accept/expect in the way of contact, and what they will want you to control/enforce.