Referee signals offside

What Is the Offside Rule in Football?

Once upon a time, the offside rule in football was a breeze to understand – if an attacking player got ahead of the defensive line to create an advantage for their team, they would be flagged offside by the linesman or woman (now known as the referee’s assistants).

But in the 200 or so years that have passed since the introduction of the rule to the beautiful game, it has been tweaked and changed so much that today it feels as though you need a map, compass and a physics degree to figure out when a player is, or isn’t, offside.

Tune into the live coverage of a game, or watch the highlights, and you can bet your bottom dollar that an offside decision will be a major talking point – often shaping the outcome of an entire match. So, come with us on a journey as we try to explain the many minutiae that govern the offside rule in football.

When Was the Offside Rule Introduced in Football?

First, a history lesson. Football has been played for hundreds of years, in various forms, and it’s thought that the offside rule was first implemented in the early 1800s. Although eyewitness reports and rulebooks were written in ye olde English, it’s possible to ascertain that a player was offside back then by simply being ahead of the ball on the attacking side of it. How pundits today would long for such black and white officiating.

At that time, football resembled something more akin to rugby with players unable to progress beyond the line of the ball, but by the middle of the 19th century the offside rule had been relaxed to allow attacking players to run beyond the ball – however, there had to be at last four players from the defending team between them and the goal.

By the late 1800s, the Football Association was becoming more influential in the governance of the beautiful game – both in the UK and overseas, where fledgling organisers of the sport looked to the FA for guidance. In 1866, they updated the offside rule so that three or more players from the defending team needed to be between the attacker and the ball in order for them to be considered onside.

Curiously, by the early 1900s the offside rule still allowed for players to be in an offside position in their own half of the pitch, should the defending team have pushed up incredibly high. By 1907, the International Football Association Board (IFAB), which still decides upon the sport’s rulebook to this day, passed a motion brought by both the English and Scottish FA that prevented a player from being caught offside in their own half of the field.

March 30, 1925 saw the most significant change to the offside rule – one that remains in place to this day. The FA arranged a trial game at Arsenal’s former Highbury home to test two amendments: a change that meant an attacking player was onside if two or more opposition defenders were between them and the ball, and that a player could only be called offside if they were within 40 yards of the opposition’s goal.

The latter was vetoed, but the former introduced in time for the 1925/26 season – it changed the face of football forever, with the likes of legendary Arsenal manager, Herbert Chapman, introducing a more attacking brand of football to coincide with the softening of the offside rule.

What Is the Offside Rule in Simple Terms?

Referee blowing whistle

Trying to produce an ‘offside rule for dummies’ style article is akin to trying to explain the possibilities of time travel to a child. In theory, the offside rule in football is simple to explain: a player is offside if they don’t have two or more players on the defending team between them and the goal. That’s the easy part.

But the rule has been tweaked over the years to change exactly which parts of the attacking player’s anatomy can be considered offside or not. In 1990, IFAB changed the offside regulations so that an attacker could be level with the second-to-last defender and be classed as onside – that wasn’t previously the case.

By 2005, the rule had been modified so that an attacking player would be considered offside if their head, body or feet were ahead of the second-to-last defender – even if other parts of their anatomy were level or behind. It was this tweak that made the offside law so much more difficult to understand; so much so that Arsene Wenger, a technical director with FIFA, wanted it to be abolished. Later, it was adjudged that no body part can be ahead of the defensive line.

And that pretty much brings you up to date with football’s offside rule. Two players must be between you and the opposition goal – one of whom can be the goalkeeper, however no ‘active’ part of your body can be ahead of the second-to-last defender.

It’s as clear as mud and one of the reasons that so many moments of controversy in football are connected to the offside rule, especially in an age of VAR zooming in to see if a player’s nostril hair or lower arm is in an offside position or not….

What Is Interfering with Play in Football?

Just when you thought you were getting a handle on the offside rule in football, along comes another caveat to make the law so much more nuanced and unclear. A player can only be offside if they are interfering with play. What on earth does that mean? Well, the FA has the following definitions of when a player is indeed actively liable when they are in an offside position:

  • Touching the ball
  • Preventing an opponent from playing the ball
  • Obstructing an opponent’s line of vision
  • Attempting to play the ball in a way that impacts a defender

Oh, and by the way, you cannot be offside if the ball cannons to the attacking player off a defender, unless the last touch is an inadvertent or accidental one.

Can You Be Offside if the Ball Is Passed Backwards?

There is a misconception that you cannot be offside if the ball is passed backwards to you. But this isn’t so: you can still be in an offside position if the ball is passed backwards, assuming that you fall foul of all of the criteria outlined in this article. There you have it: the offside rule in football.