1. Advance the Ball With Field Hockey Sticks
In field hockey, the only time any part of the body should touch the ball occurs if you are the goalkeeper. If any other player makes contact with her feet, hands or other body parts and the ball advances, the umpire may call advancing, which falls under obstruction in field hockey rules. Most umpires will not consider accidental movement as field hockey obstruction, unless the player gains some type of advantage from the accidental contact. For example, if a player uses her hands to deflect a raised ball, the team who hit the ball receives the penalty and not the player who obstructed the ball.
When a defensive player moves in to take possession of a ball, the defensive player must use his field hockey stick legitimately to snag the ball. The defensive player needs to time his tackle so his stick reaches the ball when the opponent's stick does not. If the defensive player's stick hits the offensive player's stick, the umpire will call an obstruction on the defensive player. When you tackle, you also need to avoid contact with the offensive player's body.
3. Third-Party Obstructions Lead to Field Hockey Penalties
In a third-party obstruction, a player moves between an opponent and the ball in order to prevent the opponent from tackling the ball. A third-party obstruction occurs when the player uses any part of her body including the shoulder, feet or hands or the causes her field hockey stick to obstruct the opponent. The penalty for a third-party obstruction may be a free hit or a penalty corner for the opponent's team.
4. Avoid Unfair Advantages
Most umpires strive to allow players time to play. When trying to decide when to call an obstruction, an umpire should follow the advantage rule. According to this field hockey rule, the umpire does not stop play if the penalty would give an advantage to the offending team. Some umpires only stop obstructions done in a negative manner or intentionally.
5. Let the Punishment Fit the Crime
The type of penalty awarded by the umpire typically depends upon the location of the foul. In most cases the umpire awards a free hit at the site of the foul and play continues. When a player causes an obstruction in the striking zone, referred to as the "D," the umpire awards a penalty corner instead of a free hit.