Umpire

Wikipedia - "In baseball, the umpire is the person charged with officiating the game, including beginning and ending the game, enforcing the rules of the game and the grounds, making judgment calls on plays, and handling the disciplinary actions. The term is often shortened to the colloquial form ump. They are also sometimes addressed as blue at lower levels due to the common color of the uniform worn by umpires. In professional baseball, the term 'blue' is seldom used by players or managers, who instead call the umpire by his actual name in order to show respect (and the fact that MLB umpires sometimes do not wear blue)."
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