These developments meant that catchers began to take on a crucial defensive role, as a pitcher's deceptive deliveries could only be effective if the catcher was capable of fielding them. The progression of the catcher positioning himself closer to the plate would lead to changes in pitching deliveries that would revolutionize the sport. In the 1870s, pitcher Candy Cummings was able to introduce the curveball because his catcher, Nat Hicks, fielded his position in close proximity to home plate and was able to catch the deceptive pitch. Other specialized pitches such as the spitball and the knuckleball followed, which further emphasized the defensive importance of the catcher's position.