Goalkeeper, often shortened to keeper or goalie, is one of the major positions of association football. It is the most specialised position in the sport. The goalkeeper's primary role is to prevent the opposing team from successfully moving the ball over the defended goal-line (between the posts and under the crossbar). This is accomplished by the goalkeeper moving into the path of the ball and either catching it or directing it away from the vicinity of the goal line and also becoming the so-called brick wall. Within the penalty area goalkeepers are able to use their hands, making them (outside of throw-ins) the only players on the field able to handle the ball. Goalkeepers usually perform goal kicks, and also give commands to their defence during corner kicks, direct and indirect free kicks, and marking. Goalkeepers play an important role in directing on field strategy as they have an unrestricted view of the entire pitch, giving them a unique perspective on play development. If an attacker on the opposing team obstructs the keeper from catching or saving the ball, for example, in a corner, it will normally be a free kick.
If a goalkeeper is hurt or sent off, a substitute goalkeeper has to take their place, otherwise an outfield player must take the ejected keeper's place in goal. In order to replace a goalkeeper who is sent off, a team usually substitutes an outfield player for the backup keeper (thus effectively the red card and substitution takes out two of the starting eleven players). If a team does not have a substitute goalkeeper, or they have already used all of their substitutes for the match, an outfield player has to take his place and wear the goalkeeper kit.
Goalkeepers can have longer playing careers than outfield players, many not retiring until their late thirties or early forties. For example, Peter Shilton played for 31 years between 1966 and 1997 before retiring at the age of 47.
The main squad number for a goalkeeper is number 1 but although this is still common some goalkeepers now wear other squad numbers when in goal. A good goalkeeper need good reflexes, positioning, kicking, handling and diving
Association football, like many sports, has experienced many changes in tactics resulting in the generation and elimination of different positions. Goalkeeper is the only position that is certain to have existed since the codification of the sport. Even in the early days of organised football, when systems were limited or non-existent and the main idea was for all players to attack and defend, teams had a designated member to play as the goalkeeper.
The earliest account of football teams with player positions comes from Richard Mulcaster in 1581 and does not specify goalkeepers. The earliest specific reference to keeping goal comes from Cornish Hurling in 1602. According to Carew: "they pitch two bushes in the ground, some eight or ten foot asunder; and directly against them, ten or twelve score off, other twayne in like distance, which they term their Goals. One of these is appointed by lots, to the one side, and the other to his adverse party. There is assigned for their guard, a couple of their best stopping Hurlers".〔(【引用サイトリンク】title=The Survey of Cornwall by Richard Carew )〕 Other references to scoring goals begin in English literature in the early 16th century; for example, in John Day's play ''The Blind Beggar of Bethnal Green'' (performed circa 1600; published 1659): "I'll play a gole at camp-ball" (an extremely violent variety of football, popular in East Anglia). Similarly, in a 1613 poem, Michael Drayton refers to "when the Ball to throw, And drive it to the Gole, in squadrons forth they goe". It seems inevitable that wherever a game has evolved goals, some form of goalkeeping must also be developed. David Wedderburn refers to what has been translated from Latin as to "keep goal" in 1633, though this does not necessarily imply a fixed goalkeeper position.
Initially, goalkeepers typically played between the goalposts and had limited mobility, except when trying to save opposition shots. Throughout the years, goalkeeping has evolved, due to the changes in systems of play, to be a more active role. Goalkeeper is the only position in which you can use your hands (other than during throw-ins). The original Laws of the Game permitted goalkeepers to handle the ball anywhere in their half of the pitch. This was revised in 1912, restricting use of the hands by the goalkeeper to the penalty area.
In 1992, the International Football Association Board made changes in the laws of the game that affected goalkeepers – notably the back-pass rule, which prohibits goalkeepers from handling the ball when receiving a deliberate pass from a teammate that is made with their feet. This rule change was made to discourage time-wasting and overly defensive play after the 1990 FIFA World Cup which was described as exceedingly dull, rife with back-passing and goalkeepers holding the ball. Also, goalkeepers would frequently drop the ball and dribble it around, only to pick it up again once opponents came closer to put them under pressure, a typical time-wasting technique. Therefore, another rule was introduced at the same time as the back-pass rule. This rule prohibits the goalkeeper from handling the ball again once he has released it for play; an offence results in an indirect free kick to the opposition.
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