Bullpen

In baseball, the bullpen (or simply the pen) is the area where relief pitchers warm-up before entering a game. A team's roster of relief pitchers is also metonymically referred to as "the bullpen". These pitchers usually wait in the bullpen if they have not yet played in a game, rather than in the dugout with the rest of the team. The starting pitcher also makes his final pregame warm-up throws in the bullpen. Managers can call coaches in the bullpen on an in-house telephone from the dugout to tell a certain pitcher to begin his warm-up tosses.

Each team generally has its own bullpen consisting of two pitching rubbers and plates at regulation distance from each other. In most Major League Baseball parks, the bullpens are situated out-of-play behind the outfield fence. There are currently four MLB parks with bullpens in playable foul territory: Wrigley Field, AT&T Park, Oakland Coliseum and Tropicana Field.

The origin of the term bullpen, as used in baseball, is debated, with no one theory holding unanimous, or even substantial, sway. The term first appeared in wide use shortly after the turn of the 20th century and has been used since in roughly its present meaning. According to the Oxford English Dictionary the earliest recorded use of "bullpen" in baseball is in a 1924 Chicago Tribune article from October 5. The earliest known usage of the term "bull pen" relating to an area of a baseball field is in a New York Times article from June 24, 1883. The earliest known relief pitching related usage of "bullpen" in the New York Times is in an article dated September 18, 1912.

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