Terence Crawford turned the most significant boxing match of the year into a bruising lesson in the sweet science, dropping Errol Spence Jr. three times en route to a ninth-round knockout on Saturday night to become the undisputed champion at 147 pounds.
Crawford, now 40-0 with 31 knockouts, entered the bout as the World Boxing Organization champion. In dismantling Spence, Crawford added titles from the World Boxing Association, International Boxing Federation and World Boxing Council. The win makes Crawford, 35, of Omaha, Neb., the first undisputed welterweight champion since 2007, and the first in the welterweight division to hold all four titles simultaneously.