Managers can call coaches in the bullpen on an in-house telephone from the dugout to tell a certain pitcher to begin their warm-up tosses.
Previously, in the late 19th century latecomers to ball games were cordoned off into standing-room areas in foul territory.
According to the Oxford English Dictionary the earliest recorded use of "bullpen" in relation to baseball is in a Cincinnati Enquirer article published on May 7, 1877,[1] in which writer O.P.
[2] As of the 2023 season, Oakland Coliseum and Tropicana Field are the only major league ballparks whose bullpens are located in foul territory.
[3] However, the Arizona Diamondbacks, Detroit Tigers,[4] and the Washington Nationals have since given relief pitchers the option of using a bullpen cart in the 2018 season.