Gustine was signed by Pie Traynor as a 16-year-old prospect and was 19 when he joined the Pirates as a third baseman in Traynor’s last season as manager. With his mentor gone, Gustine was shifted between second base and shortstop. His progress was also hindered by a chronic double hernia and assorted injuries. Finally, in 1947, he returned to Traynor’s old position and led NL third basemen in putouts, assists, errors, and double plays while he had his best season offensively (.297, nine HR, 67 RBI, 102 runs). He was an All-Star at second base in 1946 and at third base in 1947-48.