The Wigan forward began the first player ever to be dismissed in the Rugby League showpiece after throwing two punches at St Helens' Lance Hohaia.
Flower went demented just a couple of minutes into the game, knocking Hohaia to the ground with one punch before landing another while the stand-off lay on the ground.
This is pretty sickening stuff in a sport normally renowned for its sense of fair play.
St Helens, at least, had the last laugh as they emerged 14-6 winners, adding the Grand Final to the League Leaders' Shield win.
