Harmon Clayton Killebrew, Jr.( 1936 – 2011), nicknamed “The Killer” and “Hammerin’ Harmon”, was an American professional baseball first baseman, third baseman, and left fielder. During his 22-year career in Major League Baseball (MLB), primarily with the Minnesota Twins, Killebrew was inducted into the National Baseball Hall of Fame in 1984. Signed A.L. (Brown) ball with some toning. LOA from Todd Mueller Autographs along with our COA included.