For his first two years at Birmingham, Curtis had been used at inside-forward or on the right wing. A month into the 1930–31 season, he was switched to outside-left, and there he settled. He reached the second FA Cup final of his career in 1931 after helping his side defeat Sunderland 2–0 in the semi-final in March 1931. Curtis scored the opening goal of the game, after beating his man on the edge of the penalty area before shooting into the roof of the net, and combined with teammate Joe Bradford to force the ball over the line for his second goal later in the game. During their cup run, Bradford and Curtis scored all but one of Birmingham's 14 goals en route to the team's first ever appearance in the final; Bradford scored seven with Curtis scoring six, including another brace against Watford in the fifth round. However, he was denied a second winner's medal when his Birmingham side went on to lose 2–1 against Second Division side West Bromwich Albion in the final.