Only ever showed a yellow in my short Junior football career, one chunky lad was significantly bigger than the rest of both teams at about U8, he was kicking lumps out of other players, at that age I can accept mis-timed or clumsy but this looked cynical and after 2-3 he'd had a warning with his coach aside, after 2 more even worse it wasn't funny especially to his opponents so I yellow carded him and the coach subbed him with him bawling in tears.... No compassion from me because he was just a little bully, even at that age!!!
