Mike, I would rank the importance of positions as ff: 1) C; 2) SS 3) CF 4) 2B; 5) 3B 6) RF 7) 1B 8) LF 9) in honor of that great fielding pitcher, multiple Gold Glove winning, Hall of Famer, Jim "Kitty" Kaat, I am going to include the position of pitcher as the ninth most important fielding position in his honor. Catcher is the most important defensive position because, as you stated, pitching is the key to success. The catcher affects pitching tremendously with the catcher's pitch selection, strategy, knowledge of his pitcher's strengths and weaknesses, and the batter's strengths and weaknesses, attention to possible injuries which may be causing the pitcher problems. prevents stolen bases with a quick, accurate release and a strong arm, and as the rules stand now, with his sneaky pitch framing. Catcher is the most important defensive position.