The damage was done well before those last couple of punches. He was acting strangely prior to that and you can see he has a serious problem.
The poor kid kind of paws at the back of his head a few seconds before he inexplicably walks back and leans on the ropes as if he thinks the fight or round is over. He is clearly badly hurt and in real trouble before those final punches.
Really sad to see, but almost as sad to see people calling the other guy a murderer. He probably feels fuckin' terrible about what's happened as it is without that shit.
My heart goes out to both of them.
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