Getty Former St. Louis Cardinals manager Mike Shildt has officially retired from baseball, ending a 20-year journey that took him from the heart of the Cardinals’ system to the postseason stage in San Diego. The 57-year-old announced his decision Monday through a letter to the San Diego Union-Tribune , citing the mental, physical, and emotional toll of the sport. “The grind of the baseball season has taken a severe toll on me mentally, physically and emotionally,” Shildt wrote . “It’s time I