faltarle los suplentes y el aguatero 12
Probably is is of some game of ball or some party to dispute in which them teams have with players holders and alternates, as well as the aguatero or Waterboy, that is the person responsible of carry the water to them players drink and is cool. In Argentina, this speech the usa youth slang to indicate, figuratively, that someone is wrong of the head is missing a screw or a fool.