Full-back

The full-backs (the left-back and the right-back) take up the holding wide positions and traditionally stayed in defence at all times, until a set-piece. There is one full-back on each side of the field except in defences with fewer than four players, where there may be no full-backs and instead only centre-backs.

In the early decades of football under the 2–3–5 formation, the two full-backs were essentially the same as modern centre-backs in that they were the last line of defence and usually covered opposing forwards in the middle of the field.

The later 3–2–5 style involved a third dedicated defender, causing the left and right full-backs to occupy wider positions. Later, the adoption of 4–2–4 with another central defender led the wide defenders to play even further over to counteract the opposing wingers and provide support to their own down the flanks, and the position became increasingly specialised for dynamic players who could fulfil that role as opposed to the central defenders who remained fairly static and commonly relied on strength, height and positioning.

In the modern game, full-backs have taken on a more attacking role than was the case traditionally, often overlapping with wingers down the flank. Wingerless formations, such as the diamond 4–4–2 formation, demand the full-back to cover considerable ground up and down the flank. Some of the responsibilities of modern full-backs include:


 * Provide a physical obstruction to opposition attacking players by shepherding them towards an area where they exert less influence. They may manoeuvre in a fashion that causes the opponent to cut in towards the centre-back or defensive midfielder with their weaker foot, where they are likely to be dispossessed. Otherwise, jockeying and smart positioning may simply pin back a winger in an area where they are less likely to exert influence.
 * Making off-the-ball runs into spaces down the channels and supplying crosses into the opposing penalty box.
 * Throw-ins are often assigned to full-backs.
 * Marking wingers and other attacking players. Full-backs generally do not commit to challenges in their opponents' half. However, they aim to quickly dispossess attacking players who have already breached the defensive line with a sliding tackle from the side. Markers must, however, avoid keeping too tight on opponents or risk disrupting the defensive organization.
 * Maintaining tactical discipline by ensuring other teammates do not overrun the defensive line and inadvertently play an opponent onside.
 * Providing a passing option down the flank; for instance, by creating opportunities for sequences like one-two passing moves.
 * In wingerless formations, full-backs need to cover the roles of both wingers and full-backs, although defensive work may be shared with one of the central midfielders.
 * Additionally, attacking full-backs help to pin both opposition full-backs and wingers deeper in their own half with aggressive attacking intent. Their presence in attack also forces the opposition to withdraw players from central midfield, which the team can seize to its advantage.