I wonder... Why do almost all back-up or non-number 1 goalies: Wear 16 in France 12 in Italy 13 in Spain 18 in the USA ??? How did that come about? I mean, I'd be pissed if I were a goalie wanting to wear #15 in the states. What's worse in Spain it's a RULE for GKs to wear 1, 13, or 25. No freedom of choice there. At least in Italy they now get some choice. Some GK was wearing No. 11... two 1's ha ha very funny... Which reminds me how goofy GKs looked in the 60s and 70s wearing 2, 3, 5, 7, 8... and how goofy those 99's and 77's look now on field players... (PS: Once I saw a Mexican player wear 109... no kidding What next? Pi?)
I've seen all manner of GK numbers in MLS, the WUSA and the A-League. 0, 00, 1, 2, 12, 13, 18, and pretty much every number from 20 on up.
Just a guess: Italy #12: After #'s 1-11 this would be the first # for substitutes. France #16: With 5 subs this would be the last # available after the first 11 and first 4 subs USA #18: Just like France but using 7 subs instead of 5. Spain, well they drink too much vino to know what's going on I guess.
13 is, to my knowledge, been the traditional number for the 3nd choice keeper over here, with 22 for 3rd choice. Thought for many years 13 was avoided and he 2nd choice keeper used 15 instead.