<P> 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 . </P> <P> 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 three MLB parks with bullpens in playable foul territory: AT&T Park, Oakland Coliseum and Tropicana Field . </P> <P> 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 . </P> <P> There are numerous examples--some historical, some speculative--about the possible origin of the term bullpen . </P>

Where did the term bullpen come from in baseball