In terms of significant projects and deals, Marvin Hagler’s career was marked by his notable association with the legendary boxing promoter Bob Arum and the iconic boxing gym, the Petronelli Brothers’ Gym in Brockton, Massachusetts. The partnership between Hagler and the Petronelli brothers, Goody and Pat, proved instrumental in shaping his career and transforming him into the fearsome champion he became. Their collaboration resulted in some of the most memorable fights and victories in boxing history.