Doubleheader (baseball)

A doubleheader (in the classic sense) is a set of two baseball games played between the same two teams on the same day in front of the same crowd. In addition, the term is often used unofficially to refer to a pair of games played by a team in a single day, but in front of different crowds and not in immediate succession.

In Major League Baseball, for many decades, doubleheaders were routinely scheduled several times each season. However, today a doubleheader is generally the result of a prior game between the same two teams being postponed due to inclement weather or other factors. Most often the game is rescheduled for a day on which the two teams play each other again. Often it is within the same series, but in some cases, may be weeks or months after the original date. On rare occasions, the last game between two teams in that particular city is rained out, and a doubleheader may be scheduled at the other team's home park to replace the missed game.

Currently, major league teams playing two games in a day usually play a "day-night doubleheader," in which the stadium is emptied of spectators and a separate admission is required for the second game. However, such games are officially regarded as separate games on the same date, rather than as a doubleheader. True doubleheaders are less commonly played, and usually are of the twi-night variety. Classic doubleheaders, also known as day doubleheaders, were more common in the past, but although they are vanishingly rare in the major leagues, they still are played at the minor league and college levels.

In 1959, at least one league played a quarter of their games as classic doubleheaders, which declined to 10% in 1979 and further to the point that there were eight years between two officially scheduled doubleheaders. Reasons for the decline include clubs' desire to maximize revenue, longer duration of games, five-day pitching rotation as opposed to four-day rotation, time management of relievers and catchers, and lack of consensus amongst players.

In a twi-night doubleheader (short for "twilight-night" doubleheader), the first game is played in the late afternoon; after the first game ends, there is a break of 20 to 30 minutes, after which the second game is played. A spectator may attend both games by purchasing a single ticket. Under the Collective Bargaining Agreement, this is allowed provided the start time of the first game is no later than 5 PM, although they will generally start at 4 PM. For statistical purposes, the attendance is counted only for the second game, with the first game's attendance recorded as zero. This type of doubleheader is more common in Minor League Baseball as the result of rainouts. They are also played in Major League cities with open-air ballparks and climates that are too hot for day games.

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