Players work in pairs, sitting on the floor, with a ball between them. Their task it to receiver the ball overhand, pass it high and get up to pass the ball back.
It is easier to make this drill successful if the ball is passed high.
During this exercise body balance is being developed as players have a short time to get up.
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.