

Football is very much a team game, which has players positioned in set areas of the pitch. Each player has a specific job, attacking or defending during each phase of play. Players hold their positions or area of the field to provide the best assitance to team mates who have possesion of the ball, but also to be able to cover an attack by the oppostion.
Teams generally defend and attack as one unit, and when the play is in the opponents half most of the players are compressed into that area. However the players are still in their positions despite being further up the field.
To determine the best formation for your team you must look at the strengths of your players and decide where best to put them on the field.
11-A-Side
There are 3 predominant formations used in junior football, 4-4-2, 4-5-1 and 4-3-3. Four Four Two is the most common and popular formation used with over 90% of junior teams regularly using it over 90% of the time. Four Five One is the main alternative formation used and often during a game coaches may switch to this formation.
Four-Four-Two
This formation offers a very
balanced set of positions, with four defenders guarding the goal,
who are backed up by two wide players helping the full backs, and
two central players covering the centre backs. Having two strikers
also puts a lot of pressure on the opposition's defenders.
This classic formation offers attacking options right across the pitch with the wide players expected to use the full width of the pitch and get crosses in from the by-line. the two strikers also are on the move all the time making space by pulling defenders with them.
The central midfield players have a lot of ground to cover, both attacking and defending, and it is advisable to attack one player at a time, with the other central player sitting deeper, providing cover for the defenders.
Four-Five-One

It does rely on the midfield players quickly joining in on attacks, especially the wide players coming inside more. Having 5 players in midfield does help make a low scoring game, with only one striker there are fewer chances at goal.
this formation is often used in youth football when a team is trying to hold onto a lead.
Four-Three-Three

It is a formation little used in junior football, mainly because young players are easily confused with where ttheir position is and how it relates to their team mates.
This formation relies on a midfielder holding a more defensive position, while the otehr two midfield players suppliment the attack. When defending the two wider strikers are expected to get back behind the ball into a five man midfield.
7-A-Side
There are also three predominant formations used in mini-soccer. 2-3-1, 2-2-2 and 1-3-2. Generally 2-3-1 is the most popular formation, with most if not all teams adopting it.
Two-Three-One
This
formation gives the team a solid base and is as much about defending
the goal as it is attacking. The two defenders must keep to their
position, generally stopping the attacking striker, and also
covering any breakaway attacks.
The three midfield players are lined up along the full width of the pitch, with the central player controlling the game passing the ball out wide. The striker must move from side to side enabling an outlet ball from the wide midfielders.
When the players are defending the midfield unit must come back into defensive positions, though the striker should reamin high up the pitch occupying the opposition defenders.
Two-Two-Two

If used effectively, ie the midfield players using the full width of the pitch, it can be unsettling to the oposition in a 2-3-1 formation.
One-Three-Two

The three midfielders need to press the ball at all times and play the strikers in as often as possible, keeping the ball in the opposition half. If used correctly this formation will prduce a lot of the goals, though there is a chance of conceding many too.
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