0 used to refer to the supporters at a game between two teams of eleven players, when they give such good support to their team that they have as much value as an extra player might have:
Leeds fans pride themselves in never getting outshouted at Elland Road so they can be our twelfth man.
If there is such a thing as a twelfth man in football, Rangers will have 3,000 of them tonight.
The selection of England's twelfth man will not have been the first item on the selectors' agenda when they met over the weekend.
Even though I was twelfth man, I was so proud of the team; there was no jealousy. I kept scampering on to the pitch with drinks after every Aussie wicket fell, geeing up our bowlers.
Is there any provision in regard to a twelfth man?
Then when all else fails, it is too often the case that it is the poor commercial attaché abroad, the proverbial twelfth man, who is blamed.
The number 12 is retired in honour of the fans, also known as the twelfth man.
The most common number for this practice is 12, from descriptions of the fans as the twelfth man.