Hall of Fame umpire. ALS signed “Jocko,” 8.5 x 11, no date. Letter written on the reverse of an admirer’s letter to Conlon. In part, “I had a rule put in by Commissioner Ford Frick that anyone calling an umpire a mother F. & K. sucker a big suspension, and large fine. [Jackie] Robinson used that kind of language. Filthiest mouth in baseball.” In fine condition, with felt tip text a bit difficult to read, mild toning, and some scattered light creasing. JSA/Mike Gutierrez Auction LOA and RRAuction COA.