The guidelines were issued in a recent circular to national football federations and while they are not a rule change they will now change the handling of offside decisions.
In effect they end offside for players who do not touch the ball or directly block the vision or movement of an opponent.
The guideline should mean the end of a player not directly involved in a move being flagged for offside.
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The laws of the game state that a player can only be penalised for offside if he is "involved in active play by: interfering with play, interfering with an opponent or gaining an advantage by being in that position".
The new guidelines are more precise saying that offside for "interfering with play" means "playing or touching a ball passed or touched by a team mate".
"Interfering with an opponent" is defined as "preventing an opponent from playing or being able to play the ball, for example, by clearly obstructing the goalkeeper's line of vision or movements" or "making a gesture or movement while standing in the path of the ball to deceive or distract an opponent".
The tricky issue of whether a player is "gaining an advantage" by his position is explained as "playing a ball that rebounds off a post or the crossbar having been in an offside position" and "playing a ball that rebounds off an opponent having been in an offside position".
Serie A has operated informally with such interpretations this season and the changes have resulted in linesmen being forced to delay their decisions until the end of a move.
When players have been in a 'passive' offside position not involved in the game, the linesman's flag has stayed down but has later been raised if the player touches the ball.
The FIFA circular says the aim of the new interpretation "is to respect the laws of the game and to protect attacking play intended to result in a goal, which is the ultimate objective in football".
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