Answer: klem

AnswerCrossword Clue
KLEMHall of Fame umpire Bill who was nicknamed "The Old Arbitrator"
KLEMUmpire in the baseball Hall of Fame.
KLEMName in baseball's Hall of Fame.
KLEMHall of Fame umpire.
KLEMBaseball umpire Bill
KLEMBill of umpiring fame
KLEMUmpire in the Hall of Fame