|Diamond Jim Tannen|
|Date of birth||1850s
|Voiced by||Thomas F. Wilson
Diamond Jim Tannen was a gangster during the 1897 National League Pennant Race in Boston, Massachusetts.
Diamond Jim Tannen pressured Pee Wee McFly of the Boston Beaneaters to throw their game for his profit. Marty McFly intervened and helped Pee Wee win, which led to the arrest of Diamond Jim.