Full-back (football)

In the sport of association football, a defender is an outfield player whose primary role is to prevent the opposing team from scoring goals.

There are four types of defenders: centre-back, sweeper, full-back, and wing-back. The centre-back and full-back positions are essential in most modern formations. The sweeper and wing-back roles are more specialised for certain formations.

A centre-back (also known as a central defender or centre-half) defends in the area directly in front of the goal, and tries to prevent opposing players, particularly centre-forwards, from scoring. Centre-backs accomplish this by blocking shots, tackling, intercepting passes, contesting headers and marking forwards to discourage the opposing team from passing to them.

With the ball, centre-backs are generally expected to make long and pinpoint passes to their teammates, or to kick unaimed long balls down the field. For example, a clearance is a long unaimed kick intended to move the ball as far as possible from the defender's goal.

During normal play, centre-backs are unlikely to score goals. However, when their team takes a corner kick or other set pieces centre-backs may move forward to the opponents' penalty area: if the ball is passed in the air towards a crowd of players near the goal then the heading ability of a centre-back is useful when trying to score. In this case other defenders or midfielders will temporarily move into the centre-back positions.

In the modern game, most teams employ two or three centre-backs in front of the goalkeeper. The 4–2–3–1, 4–3–3, and 4–4–2 formations all use two centre-backs.

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