Boxing used to be a big time sport, especially heavy weight boxing, before unbelievably venal, greedy, sociopathic promoters (Don King lead the pack) killed it. And Ken Norton was one of the best. Ken Norton handed Muhammad Ali his second career defeat in their first meeting. Then he officially lost two subsequent but very close matches that could have gone either way. In his day, he was a match for Ali, more so (IMO) than Joe Frazier.
He was hospitalized before he died, and I can only speculate that he may have been one more victim of pugilistic brain damage.
He was one of the greats.