All substitutes dream of coming onto the pitch and making that game-changing intervention which makes them a hero.
Unfortunately this substitute simply couldn't wait to actually be officially involved in the match before making that contribution, running on from behind the goal to stop a shot from hitting the net.
The referee then applied the letter of the law: the substitute was sent-off (although this would not have affected anything numbers-wise) and gave an indirect free kick to the attacking team. Unfortunately for them, the resultant shot was blocked, so no goal was given.
You have to feel that justice was not really done here - if this had been in Brazil, there'd have been a riot.