Now This, This Is Pain
For my American readers, imagine running full speed straight at your friend, who is also running full speed at you, both of you are holding pillows up in front of yourselves. You will smash into each other with extraordinary force, you will knocked half senseless, you will probably be left so winded you'll feel like puking and shitting your pants at the same time.
Now do it again, without the pillows.
This is how you play football in Australia.