Scrum half back

A rugby league football team consists of thirteen players on the field, with four substitutes on the bench. Each of the thirteen players is assigned a position based on both the role they are expected to fill within the team and the area they typically occupy on the field. These positions are defined by number and are standardised across all teams and matches, however the same rules apply equally to all players regardless of position and the positions are fluid, meaning players free to interchange between positions or take up a different position at any time. In practice, the positions simply serve as a guideline as to the player's expected role in both attack and defence.

Players are divided into two general categories, forwards and backs. Forwards are generally chosen for their size and strength. They are expected to run with the ball, to attack, and to make tackles. Forwards are required to improve the team's field position thus creating space and time for the backs. Backs are usually smaller and faster, though a big, fast player can be of advantage in the backs. Their roles require speed and ball-playing skills, rather than just strength, to take advantage of the field position gained by the forwards. Typically forwards tend to operate in the centre to the field, while backs operate nearer to the touch-lines, where more space can usually be found.

The laws of the game recognise standardised numbering of positions. The starting side normally wear the numbers corresponding to their positions, only changing in the case of substitutions and position shifts during the game. In some competitions, such as Super League, players receive a squad number to use all season, no matter what positions they play in.

The positions and the numbers are defined by the game's laws as: ه

There are seven backs, numbered 1 to 7. For these positions, the emphasis is on speed and ball-handling skills. Generally, the "back line" consists of smaller, more agile players.

Numbered 1, the fullback's primary role is the last line of defence, standing behind the main line of defenders. Defensively, fullbacks must be able to chase and tackle any player who breaks the first line of defence, and must be able to catch and return kicks made by the attacking side. Their role in attack is usually as a support player, and they are often used to come into the line to create an overlap in attack. Fullbacks that feature in their respective nations' rugby league halls of fame are France's Puig Aubert, Australia's Clive Churchill, Charles Fraser, Graeme Langlands and Graham Eadie, Great Britain/Wales' Jim Sullivan and New Zealand's Des White.

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Wikipedia