A knock-on occurs when a player loses possession of the ball and it goes forward, or when a player hits the ball forward with the hand or arm, or when the ball hits the hand or arm and goes forward, and the ball touches the ground or another player before the original player can catch it. ‘Forward’ means towards the opposing team’s dead ball line.

 

The referee would give the opposing team a scrum when the ball is knocked forward by the team in possession, for example at a ruck when the scrum half goes to pass the ball and he fumbles as he is picking it up and drops it. Or if you fail to catch the ball and it falls in front of you.

 

However, if you purposely hit the ball fowards when intercepting the ball the referee will award a pentalty to the other team and possibly give you a yellow card. the referee will also have to deliberate weather the team could have scored a try before the ball was intercepted and may award a penalty try.