The American Football Analogy
Most people are somewhat familiar with American football, so let’s use that as our foundation. The offside line is where ever the second most forward defensive player is standing, in almost every case this is the defensive player in front of the goalie. Now, let’s make some analogies. Think of the offside line as the line of scrimmage and the player with the ball as the quarter back. The QB can pass the ball as much as he wants until he crosses that line, at which point the pass can only go backwards. It’s essentially the same thing in soccer, you can pass the ball backwards and perfectly sideways all you want. But in order to go forward the pass has to be made before the receiver crosses the line of scrimmage, or in soccer terms the offside line.
The Confusion and Exceptions
The confusion typically sets in with the combination of a well timed through pass played in behind the defense, and a perfectly timed run by the attacking player. For most, this would appear offsides as the attacking player is receiving the pass with no defenders close by. However, the player receiving the pass was onside when the pass was made and is therefore onside.
It is not an offense for a player to be standing in an offside position if he is not involved in the play. If a player is standing in an offside position and receives a pass, he becomes involved in the play and is therefore offside. If a player is offside and obstructs a defender who is chasing a player attacking from an onside position, he becomes involved in the play and offsides will be called.
- You cannot be offside on a throw in: The ball is technically not on the field of play or live until it touches the receiving player.
- You also cannot be offside on a corner kick: The ball is placed on the touchline, therefore once the ball is kicked in to play it is going backwards and the recipient is therefore onside.
- You cannot be offside on a goal kick: You are not the team in possession and the ball is dictating your offside line.
- You can’t be offside if you’re in your own half: Otherwise you’d have an entire team standing in front of the other teams goal.
What’s the point of the offside rule?
If it weren’t for the offside rule you would have forwards standing in front of their opponents goal waiting for a long pass in and an easy shot on goal. Or, as it’s referred to in the game, “cherry picking.”
Diagrams
If you still need further explanation, pictures are worth a thousand words. So, let’s see if these help.

The blue team has possession of the ball (represented by the white dot next to the blue dot towards the top center of the diagram) and is attacking the red goal on the left side of the diagram. The blue player furthest left is in an offside position as he is in front of both the second-to-last defender (highlighted by the dotted line) and the ball.

No blue players are offside in this diagram because the ball is dictating where the offside line is for the blue team.