One linesman patrols each sideline. They change sides at half-time.
At every match one of the linesmen holds the position of standby referee.
What are the Duties of the Linesman?
The linesman indicates by flag signal:
When and where a ball crosses the sideline
Which side is entitled to the sideline kick or puck, and
Where the kick or puck is to be taken from
Powers of Linesmen
The linesman has the power to bring to the attention of the referee, during a break in play, any instances of foul play or incursions onto the field of play which have not been noticed by the referee. It is the duty of the linesman to report any such instances and his obligation is to do so by providing the factual situation regarding the instance.