Why in the world would you do this? Has nothing to do with rugby that I can make out. So, since it is violent conduct contrary to the spirit of the game, yes, you could be red-carded. And because it is outside the laws and traditions of the game, you might be liable for damages if you injured the other player (at least in the States). Need to convince yourself that you are a real tough guy? Join the Marines. But if you take this sort of attitude in, you will wash out. That's a fact. A better idea would be to grow up, hopefully quickly. mark L.
