The Rational Ref | Fifa revisits offside rules

The much-quoted saying "If he's not interfering with play, what's he doing on the pitch?" is usually incorrectly attributed to former Liverpool manager Bill Shankly instead of Tottenham Hotspur manager Bill Nicholson.

Although decades old, it refers to the essence of the offside law, which is to penalise a player for being in an offside position when he is involved in active play.

The problem is the exact definition of being "involved in active play". This has generated much derision, denunciation and debate among disgruntled managers, players and supporters when a team are obviously disadvantaged by conceding a goal due to a contentious offside call.

The offside rule defines active play as either interfering with play, interfering with an opponent, or gaining an advantage by being in that position. Over the years, these three seemingly straightforward statements have been misunderstood, misrepresented and misinterpreted.

An example occurred on Boxing Day last year when Manchester United were on the unfavourable end of a non-offside decision since Newcastle United's second goal was attributed as an own goal.

This was when Manchester United defender Jonny Evans stuck out his leg and diverted a Newcastle United cross into his own net. Controversy ensued because as the cross was played in Newcastle forward Papiss Cisse was in an offside position. However, a player being in an offside position is not an offence in itself. The consideration here is whether Cisse was involved in active play.