With his 12th-round TKO of Miguel Cotto in November, Manny Pacquiao, above, has won championships in seven different weight classes. (Isaac Brekken/Associated Press)
Middleweight champion Sugar Ray Robinson was, in actuality, a hybrid: a boxer, but also an assassin of his opponent's mind-set. Presenting an excerpt of a new biography by author Wil Haygood.