Sometime the sparring rule can be misleading. Even if the rule doesn't allow head punch, but if you use your head to block my punch (this had happened so often in no head punch rule), is that your head problem, or my fist problem?
If you send inter-continental missile to attack my country, do I have the right to use my defense missile to shot your missile down?
If you throw a
- punch, your opponent gives you a hard block on your arm,
- front kick, your opponent drops his fist on your toes,
- side kick, your opponent drops his elbow joint on your instep,
- low roundhouse kick, your opponent turns his shinbone into your kick,
who's fault is it? You attack him. He just play defense and protect his territory.
In the following clip, the downward block is designed just for that purpose - to block a front kick.