Pete, in answer to the blood, in all codes of sport here they have what the call a blood rule.
This means the player has to leave the field of play if there is any sign of exposed blood anywhere on the body, and not allowed back on the field of play until the bleeding has stopped. Was bought is a few years ago. I think it was classed as health and safety issue in relation to catching Hep A,B,C and Aids from anyone that was infected.
If it was Rugby League, most of the tackles I see here are mainly made between the waist and top of the shoulders, mainly I think to try and make sure that the tackle is made 100%, in league if the tackle is not made correctly it is not counted in the six tackle count and can be a big advantage to the attacking team.
In none of the Rugby or AFL Codes are you allowed to tackle anywhere round the head (Englands Adrian Morely Still Has Not Learnt That Yet). In League you can be sent from the field for the whole game or put in the sin bin for 10mins.
Not sure in Union, may be the same thing
In AFL you get reported and then they have the option to suspend you if found guilty.
In relation to the kicking of the ball, if it is league u are watching, if you have had 5 tackles made on your team, if you get caught in possesion when the 6th tackle is made, the ball is automatically turned over to the other team.
What they are doing is trying to feed the ball to one of their team to run ono to try and score a try without being tackled again, or they put the ball high up in the air hoping that the opposition fumbles the ball.
If that happens, the attacking side gets the ball again and have a fresh set of 6 tackles to attack with again.

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