While playing for Marianao in 1952-1953 McDuffie had the misfortune to play for manager Dolf Luque, a former major league pitcher who was notorious for his bad temper and conflicts with other people.
His most productive season in Cuba came with Cienfuegos in 1944-1945, when he posted a 7-6 record and a league's second-best 2.35 ERA in 20 games, while leading in complete games (9), strikeouts (68), walks (43), and innings pitched (138).