Let us now dissect that second Oranje goal and see why it shouldn't have stood. But let's first explain what "offside" means.
According to the Laws Of The Game, a player is in an offside position if he is nearer to his opponents’ goal line than both the ball and the second-last opponent. But it is not an offence in itself to be in an offside position.
This essentially means that a player can stay near the opposition goalkeeper throughout the 90 minutes, but he will not be deemed offside unless at the moment the ball touches or is played by one of his team, he is, in the opinion of the referee, involved in active play by:
a) interfering with play or
b) interfering with an opponent or
c) gaining an advantage by being in that position.
But a player is not in an offside position if:
a) he is in his own half of the field of play or
b) he is level with the second-last opponent or
c) he is level with the last two opponents
Now let us apply these rules to Wesley Sneijder's goal.
When Sneijder took the shot on the Uruguayan goal, striker Robin Van Persie was (apparently) in line - to the assistant referee - with defender Diego Godin, who was the second-last opponent (the last one is the Uruguayan goalkeeper Fernando Muslera). However, TV replays showed that his right foot was beyond the line, and according to the interpretation of the laws, the Arsenal striker was in an offside position, as a part of his body with which it is legal to score a goal was beyond the second-last defender.
Now, Sneijder took an attempt on the Uruguayan goal rather than try to pass the ball towards Van Persie. So in an ideal situation, Van Persie wouldn't have been in an offside position had he just allowed the ball to go past him. Suppose Sneijder's shot hadn't taken a deflection off Maxi Pereira and had gone in, then the Dutch striker wouldn't have been deemed to be interfering with the play and the goal would have been legitimate.
But the ball did take a deflection towards Van Persie, who apparently tried to turn the ball home with his right foot, which directly denotes that the 26-year-old was interfering with the play - this is an offside offence.
Even if for argument's sake, we take it that Van Persie was just letting the ball move by removing his leg from its path, he was still interfering with play. The Arsenal striker was directly in front of Muslera and was blocking his sight of vision, therefore putting Muslera at a disadvantage and interfering with play. The Dutchman was in an 'active' state of play at the time.
All of which points to the fact that Van Persie was in an offside position. Of course, the entire hypothesis is based on the fact that the positioning of his right foot placed him in an offside position - this is, in turn, based on the interpretation that for a player to be deemed onside, his entire body should be in line with the second-last opponent.
Once again a controversial decision left an ever-lasting impact on a game's result. Not that you can entirely blame the referee's assistant: after all, we - all those not on the touchline dressed in black with a flag in one hand - have the luxury of watching the video over and over again, while the poor referee has just one chance to make his decision.
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