Football (Offences) Act 1991Just at Pro games. It is a criminal offence to enter the playing field or it's perimeter.
Dog & Duck won't actually have any spectators, so it's a mute point (or is that the Black Swan?).
4. Going onto the playing area
It is an offence for a person at a designated football match to go onto the playing area, or any area adjacent to the playing area to which spectators are not generally admitted, without lawful authority or lawful excuse (which shall be for him to prove).
"Designated footall match"?
In this Act a “designated football match” means an association football match designated, or of a description designated, for the purposes of this Act by order of the Secretary of State.
Any such order shall be made by statutory instrument which shall be subject to annulment in pursuance of a resolution of either House of Parliament.