The Offside Rule explained

It's arguably the most contentious law in football and not even the paid experts demonstrate a clear understanding. Read this, and then quote it back verbatim when the liney rules out that perfectly good second goal this season . . .

Keith Hackett
The Observer
Last weekend's Match of the Day criticised the offside law. Questioning Jérémie Aliadière's valid goal for Middlesbrough against Arsenal, they made a wider point, which I've heard before. Match officials can't work with or understand the modern offside law: if you had 10 referees in a
room, they said, you would get 10 different decisions.

Let's be clear about this. Match officials do know the laws and apply them to the best of their ability - but time and again pundits criticise perfectly valid decisions. The Match of the Day analysis of the Aliadière decision was a case in point. They suggested the goal should not have been given, that the striker should have been flagged for 'gaining an advantage' after being in an offside position from the long ball. That is simply wrong.

It is immensely frustrating. The law, clarified by the International FA Board in 2005, is a good, effective one, but it seems to have totally eluded some in the media. Officials understand it perfectly, and so could the lads in the studio if they wanted to - it's set out in black and white for anyone who can find the time to read it. Many pundits do a great job, but I hope they respect my right to point out when they are misleading fans, and winding themselves up with old or wrong information.

The law really is simple and well defined. First and foremost, it is important to know the key principle: it is not an offence in itself to be in an offside position. Assistants will not flag the moment someone strays offside. A player is only penalised if he then becomes active.

The source of most confusion is clearly in the definition of 'active'. Pundits keep falling back on the dictionary definition of the word, or their own version of it, rather than the one set out in the laws. It's intensely frustrating to see them spreading misinformation - misinformation that leads to the sort of abuse that drives officials out of the game.

To be clear, the definition, in the laws, is this: in deciding whether to flag, assistants must watch out for three things, any one of which would make an offside player active.

First, is the offside player interfering with play? As advised by the IFAB since 2005, that means playing or touching the ball. Attempting to play the ball does not count - he must actually play or touch it.

Second, is the player interfering with an opponent's ability to play the ball, by clearly obstructing the opponent's line of vision or movements, or by making a gesture or movement which, in the opinion of the referee, deceives or distracts an opponent?

And third, is the player 'gaining an advantage'? This last point is specific, and is not what Match of the Day seem to think it is. It applies only to an offside player playing a ball that rebounds to him from an opponent, the post or the crossbar. If he does not play the ball from the rebound, then he is not penalised for being in that offside position. Nothing else counts as 'gaining'.

And that's it. If a player ticks any one of those three boxes, he is offside. The three-part definition is remembered as 'PIG' - if a player doesn't Play, Interfere or Gain, he is fine.

The law is a real positive for the game - the pundits should love it. The active definition helps games flow - there are fewer stoppages for offside now - and it makes negative play far less profitable. No sensible team today uses the arms-aloft offside trap made famous by George Graham's Arsenal (Ed - boo hiss) in the 80s and 90s. That trap was totally against the spirit of the offside law - it was never intended as a device for earning cheap free-kicks. The active system means that the offside trap is now a dangerous tactic to use and allows the benefit of
the doubt to be always with the attacking team.

Of course, the fact that the law is unambiguous does not put an end to split-second mistakes, and we will always try to learn from them and improve. When officials do get it wrong, for example in the Manchester City v Tottenham game last Sunday, or in the same Arsenal v
Middlesbrough match when Emmanuel Adebayor was wrongly given offside, we can expect criticism, and the officials concerned are given operational advice. My point is that pundits' criticism of officials should at least be fair and informed, based on a proper knowledge of the laws, not on some vague idea of what they might be. If I hear one more co-commentator
criticise an assistant referee for a 'late flag' - when the assistant is clearly waiting to see if an offside player ticks any of the three PIG boxes - my TV will go out of the window.

I'm honestly very proud of the officials who put themselves forward for what is a thankless task. They are hard-working, dedicated and honest, and deserve so much more respect than they get. All I'm asking is that pundits and phone-in critics read the laws before complaining. Failing
that, if they really do know better, they should step forward, sign up and have a go themselves.

Keith Hackett is general manager of Professional Game Match Officials Limited

The 'active' system: case studies

Blackburn v Liverpool
April 2006

Robbie Fowler chests the ball towards Fernando Morientes, who is onside. But Djibril Cissé, in an offside position nearby, with no defenders around him, sees the ball coming his way, and raises a leg to play it. However, he stops himself just in time, realising he would be flagged for being involved in active play if he made contact. The ball runs on to Morientes, who crosses back to Fowler, who scores. Defenders protest, but the decision is correct. Cissé did not play the ball. 'Attempting to play the ball' does not count. He did not interfere - there were no defenders near him - and he didn't gain an advantage (there was no rebound).

Manchester City v Blackburn
December 2007

Blackburn cross from the right: the ball goes over the head of David Dunn, in an offside position, and reaches Roque Santa Cruz, running from an onside position, who scores. The assistant referee flags Dunn offside - but quickly realises Dunn wasn't active: he didn't play the ball,
interfere with an opponent, or gain an advantage. The assistant calls the referee over, explains why the goal should stand, and the referee agrees. This example shows the importance of assistants not being too quick to flag.