The fullback is numbered 1. This position needs all-round ball-playing ability and speed. The fullback is the last man in defence standing behind the main line of defence. As they are typically positioned behind the first line of defence and have a view of the entire line, good fullbacks will give orders to the other defending players, alerting them to fill possible holes and weaknesses in the line. From their position behind the main line of players, good fullbacks watch for both teams' defensive deficiencies and offensive opportunities as they appear throughout a game. Experienced fullbacks therefore are sometimes moved to the five-eighth position later in their career to utilise this knowledge in reading gameplay. An example of this is Darrren Lockyer who is now regarded as one of the greatest five-eighths.
Their role in attack is usually as a support player to take an offload and keep the ball alive, or to provide an overlap or a different angle of attack in the centre of the field. They may also act as a third receiver.
Fullbacks must be ready to chase down and tackle any player who breaks the first line of defence and catch the majority of kicks made by the attacking side, ensuring possession is retained.