Mike Shildt is retiring after two seasons as the San Diego Padres' manager. The Padres confirmed the 57-year-old Shildt's decision Monday. In a letter to the San Diego Union-Tribune, Shildt said he is retiring because the grind of the baseball season has taken a severe toll on me mentally, physically and emotionally. Shildt went 183-141 and led San Diego to two postseason appearances during his brief tenure.