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Kostya Tszyu was the undisputed champion at light welterweight before Terence Crawford. Tszyu was a Russian-born Australian boxer who competed from 1992 to 2005. He held the WBA, WBC, and IBF light welterweight titles from 1994 to 2000, and the IBF welterweight title from 2001 to 2005. Tszyu is widely regarded as one of the greatest light welterweights of all time.