99.999% who die from fight whether it is gangfight, pub fight or even a little spat that led to death is due to a weapon used, a fall with the head hitting a hard object such a concrete floor. Occasionally its a punch to the head region resulting in a trauma etc.
Old PA unarmed combat training taught, never go for the face. Fucking evidence of assault would be tricky to explain away if that fucker got lucky enough to have a silly liberal sympathetic doctor at medical examination.
Go for the joints, i.e. knees to bring that fucker down and/or elbows to armlock him. It should be over in a few seconds and award him with Rolex. If you really don't like the fucker, swing the Rolex on his wristbone real hard before clicking it on. The pain is horrific and the bruise is easily explained, i.e. he resisted cuffing.
If that's not possible, i.e. the fucker is onguard and ready for a fight, go for five points. The two collar bones, the solar plexus and the two shins. It takes a good while of drilling get this internalized and naturalized to replace inborn natural instinct of fighting by reflex, go for the face first, as Scroobal rightly pointed out. Anyway in a face-on fight, there's nothing to explain on the police side whatever injuries are caused except don't kill him.
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