How is this controversial? Fighter A slips and is obviously not on his feet. Fighter B sees Fighter A has fallen, winds up, and blasts Fighter A with a punch.

What has gone on in other fights under similar situations is irrelevent.

If you see a fighter is not on his feet you cannot hit him. Hey, if you knock an opponent down, why not stand over him and hammer his head with your fists if the ref hasn't stopped you? To use the excuse that the ref hadn't yet stepped in is ludicrous. Any fight when an opponent has taken a knee should get a DQ victory if the other fighter hit him while he was down. Cheating in the past doesn't vindicate cheating in the present. If I recall correctly, in the Cotto fight, Margarito was about to punch him when he took a knee. It wasn't like Cotto took a knee THEN Margarito wound up and punched. Dirrell fell, THEN Abraham pulled back and threw.

Why is it so odd for some to think that a flush punch from a hard puncher could discombobulate an opponent who was in no way prepared to be punched?