Players put a hat on their head, while the coach feeds balls to the player. They must execute a forehand volley without the hat falling off their head.
In this drill, the player works on their head stability. Having a hat on the head is a visible indicator of success or failure. Firstly, the player learns how to hit without moving, before potentially adding movement to the drill to make it more challenging.
Having an unstable head is a reason for many mistakes, not only at the net but also when executing strokes on the baseline. Controlling the head is a necessity to improve body control and the effectiveness of the stroke.
World Rugby has reportedly conceded Aaron Smith's disallowed try in the World Cup final should have stood.
"It is not only useful for staff who are experienced but a valuable tool for those subject staff who have to take teams."
The variety of sessions across sports - sometimes we steal session ideas from one sport and use them with another.