Robin van Persie scored the equalizing goal as Manchester United drew 2-2 with West Ham United on Wednesday in a thrilling English Premier League match. The goal, however, probably shouldn't have counted.
Van Persie's goal helped United avoid defeat, but in the context of the season, it did little else. With the draw, United remained well ahead of City in the title race; with a loss, the Red Devils still would have been the overwhelming favorites.
Even so, West Ham manager Sam Allardyce fumed about the decision after the match, lamenting the loss of a "famous victory" for his side.
Allardyce said (h/t 101 Great Goals): "It's a bit difficult to take when that's their job—their job is to give the offside decisions when they appear in front of them. And this is a blatant one."
For his part, Manchester United manager Sir Alex Ferguson played coy. "Really?" he said in a post-match interview. "Well, I didn't see that to be honest with you."
So who's right? Does Allardyce have a gripe? Let's look at the incident in detail.
The incident happened in the 77th minute and started with United's Shinji Kagawa. The Japanese midfielder cut inside along the edge of the box and curled his shot—it took a deflection along the way—off West Ham's upright. The ball rebounded to van Persie, who buried his shot for his 21st league goal of the season.
The sequence can be seen in the GIF below:
Now comes the tricky part.
When Kagawa took his shot, van Persie was in an offside position. That is not in question. The questionable part of the decision was whether van Persie was active at the time.
Here is a view of the line around the moment Kagawa took his shot. Van Persie is the white-shirted player beyond the offside line near the middle of the image:
If you argue that van Persie was not active when Kagawa shot, then United's goal should stand. If, however, you consider him a threat in the box—as I do—when Kagawa took his shot, then the goal should have been ruled out.
Either way, it was a difficult call for the linesman, who had to decide in a split second not only whether van Persie was offside, but also whether he was active at the time of the shot. It's worth pointing out that goal-line technology might have indirectly eased the assistant's task by taking the burden of watching the goal line off him.
Freed from that responsibility, the linesman's only duty would have been watching West Ham's defensive line and Manchester United's attackers for a potential offside. Then again, this was an especially difficult, split-second decision.
What do you make of it? Should they goal have stood? For me, it was offside and should not have counted.