Football Players Then And Now

A game is officiated by a referee, who has "full authority to enforce the Laws of the Game in connection with the match to which he has been appointed" (Law 5), and whose decisions are final. The referee is assisted by two assistant referees. In many high-level games there is also a fourth official who assists the referee and may replace another official should the need arise.
Pitch
As the Laws were formulated in England, and were initially administered solely by the four British football associations within IFAB, the standard dimensions of a football pitch were originally expressed in imperial units. The Laws now express dimensions with approximate metric equivalents (followed by traditional units in brackets), though popular use tends to continue to use traditional units in English-speaking countries with a relatively recent history of metrication, such as Britain.