BTW:
Sheffield Wednesday's pitch is the absolute maximum size, as are the pitches at their training facility. Jack Charlton once phoned me up to ask if I'd referee a selection match on one of those (very big) training pitches.
South Yorkshire Under-18 squad were playing the Sheffield Youth squad. Every one of those players was on the books of professional teams (with several of the South Yorkshire players signed to Manchester United) and, at that age, were about as fit as it's possible to be. Further, they were all trying to be selected for either the County youth team or Sheffield Wednesday's team, so they were putting everything into it.
I knew that I'd find the game exhausting but what Jack hadn't told me was that:
(a) the match would be played on the hottest day of the year ;
(b) the selection process was to be carried out over THREE 45 minute periods, with no interval between them ; and
(c) there were 33 players on each side, so that a fresh squad of 11 super-fit teenagers would play in each of those periods (while poor old muggins here had to keep going!).
I've hardly ever been as tired in my life as I was after that match!
(At least Jack was always good at providing ample free booze for those who he asked to do favours for him!)