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In the sport of association football, each of the 11 players on a team is assigned to a particular position on the field of play. A team is made up of one goalkeeper and ten outfield players who fill various defensive, midfield, and attacking positions depending on the formation deployed. These positions describe both the player's main role and their area of operation on the pitch.

In the early development of the game, formations were much more offensively aggressive, with the 1-2-7 being prominent in the late 1800s. In the latter part of the 19th century, the 2–3–5 formation became widely used and the position names became more refined to reflect this. In defence, there were full-backs, known as the left-back and right-back; in midfield, left-half, centre-half and right-half; and for the forward line there were outside-left (or left wing), inside-left, centre-forward, inside-right and outside-right (or right wing). As the game has evolved, tactics and team formations have changed and so many of the names of the positions have changed to reflect their duties in the modern game (though some old familiar ones remain). The term "half-back" fell out of use by the early 1970s and "midfield" was used in naming the positions that play around the middle third as in centre midfield and wide midfield.

The fluid nature of the modern game means that positions in football are not as rigidly defined as in sports such as rugby or American football. Even so, most players will play in a limited range of positions throughout their career, as each position requires a particular set of skills and physical attributes. Footballers who are able to play comfortably in a number of positions are referred to as "utility players".

However, in Total Football tactics, the players are only loosely defined into a position. This tactic required players who were extremely versatile, such as Johan Cruyff, who could play every position on the pitch apart from goalkeeper.

Goalkeeper is the most defensive position in football. The goalkeeper's main job is to stop the other team from scoring by catching, palming or punching the ball from shots, headers and crosses. Unlike their team-mates, goalkeepers typically remain in and around their own penalty area for most of the game. As a result, goalkeepers have a better view of the pitch and often give advice to their defence when the other team is on the attack or during set pieces. Goalkeepers are the only players on the pitch who are allowed to handle the ball, but this is restricted to their own penalty area. Positioning is another important job and is one of the hardest to master as keeper.

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