St. Louis, MO-St. Louis Cardinals pitcher Chris Carpenter officially announced his retirement from Major League Baseball on Wednesday. Carpenter, who’s 38, spent 16 years in the majors. He missed all of last season with nerve issues in his right shoulder. The Cardinals announced they gave manager Mike Matheny a three-year extension that keeps him in St. Louis through 2017. Matheny guided the Cardinals to the National League Championship Series in each of his first two seasons.