SIGNALLING A DEAD BALL

The dead ball is called for a number of reasons, when someone is injured and either the players or the umpire require medical attention, for example.

Umpires would make the same signal if a batsman steps away from his crease when he is not ready to receive the delivery.

Likewise, if the bowler loses his run-up and stops before letting go of the ball.

That signal is the crossing of the wrists below the knee and the delivery should recommence without the original one counting.