Following the 1941 season, Cardinals general manager Branch Rickey traded future Hall of Fame first baseman Johnny Mize to the New York Giants, opening a spot for Sanders. Sanders made his MLB debut for the Cardinals on April 14, 1942. He and Johnny Hopp split time at first base through mid August, with Hopp receiving the lion's share of playing time from that point on, as well as starting all five games in the 1942 World Series, which the Cardinals won over the New York Yankees.