This is a defensive maneuver on the field that is quite legal and is one of the few contact moves allowed. A player attempts to ruin an opponent’srun with the ball by bumping his horse against the other player’s. This bump, which can rattle teeth, is regulated by the angle at which the aggressor attempts it. It can never be more than 45 degrees, and the faster the horses are running, the smaller the angle. It is obviously a rough one for the umpires to call, as well.
In an attempt to thwart an opposing players Intention of hitting the ball, a player may put his mallet out to either hook the opponent’s or simply block the swing. This is legal as long as the “hooker” is on the same side of the opponent’s horse as the ball.
One of the most common penalties is where one player crosses in front of the one with the ball. This is called“crossing the line”. The line is an imaginary path, running the full length of the field, in which the player with the ball is running. No player can go across this.