TheRef tells it like it is:
OK, here’s a hint kiddies: if a guy is doing anything illegal "all game
long", the wrong time to tell the referee is after the final whistle. I
thought that this would be self-evident, but apparently it’s not. It
leads us referees to believe that, hmmmmm, you just lost a game that
you were ahead of for 80% of, could you be trying to blame the referee
instead of your own play?