What is the offside rule in soccer?
A player is offside if they're ahead of both the ball and the second-last defender at the moment a teammate plays the ball to them.
It's Friday night outside the bar. You've stepped out to take a call and when you turn around there's a line, and Big Tony is checking IDs.
You reach for your wallet. It's on the bar. Your mate John is still inside nursing his pint, so you ring him to bring it out.
Here's the question. Do you:
A) Go to the back of the line, take your ID from John, and show it to the bouncer when it's your turn.
B) Skip the entire line, take your ID from John, and show it to the bouncer ahead of the four people who were waiting before you.
Pick B and you have just been caught offside.
The actual rule
A player is offside if, at the moment a teammate plays the ball to them, they are nearer to the opponent's goal line than both the ball and the second-last defender.
Two details do all the work in that sentence.
“The second-last defender” usually means the goalkeeper plus one outfield player. The keeper counts. That's why you'll hear people say you have to keep two players between you and the goal.
“At the moment the ball is played” is the part everyone gets wrong. It doesn't matter where you are when you receive the pass. It matters where you were when it left your teammate's foot. A player can be miles beyond the defense by the time the ball reaches them and still be perfectly onside, because they timed the run.
That's why the assistant referee stands level with the defensive line and stares sideways rather than watching the ball.
When you can't be offside
In your own half.
From a throw-in.
From a goal kick.
From a corner.
That last one surprises people. You can stand anywhere you like at a corner. Nobody is ever offside from one.
Why the rule exists at all
Without it, you'd park your fastest striker next to the opposing goalkeeper and boot the ball forward for ninety minutes. Every game would be a punting contest.
Offside forces teams to move up the field together, which is what makes build-up play, pressing, and defensive lines possible. It's the rule that makes soccer look like soccer.
It's also why a defense will sometimes step forward as one, arms in the air, trying to catch an attacker on the wrong side of the line. That's the offside trap, and when it goes wrong it goes very wrong.
Related Terms
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