I've seen that, but it doesn't show any of the previous incident that this was considered retribution for.
Looking at the crowd, I reckon it's because, they seem to have weeded out the oap's and kids and stuffed away fans in the upper tier.
The FA obviously thought otherwise and having not seen what they've seen, I'm in no position to comment.
He was running back from the offside position, and only picked up the ball slightly later from what I remember seeing.
It was a correct decision...just it looked initially ok as the long clearance by the keeper & his run back didn't appear on the TV shot together. Well done linesman.
As there's nothing malicious in this tackle, whatever went on before this tackle should be irrelevant.