Baseball was one of the first-ever baseball sports games, and was created on a PDP-10 mainframe computer at Pomona College in 1971 by student Don Daglow.[1] The game (actually spelled BASBAL due to the 6-character file name length restrictions) continued to be enhanced periodically through 1976. The program is documented at the Baseball Hall of Fame in Cooperstown, New York.
Its sabermetric style mathematical models were the basis for many later commercial baseball video games over the next three decades, including Intellivision World Series Baseball (the first video game to use multiple camera angles) (1983), the Earl Weaver Baseball series (1987–1991) and the Tony La Russa Baseball series (1990–1997).
A version of Baseball was distributed by the Digital Equipment DECUS file sharing network in 1972 to a handful of universities and other PDP-10 sites, but it fell far short of the popularity of Daglow's 1972 Star Trek.
The distributed version of the game printed the results of each play on a piece of paper in the computer terminal. Two human players could oppose each other, one person could play against the computer AI, or the computer could manage both teams and complete the game without human intervention.
At the start of each inning the batter's and pitcher's names were listed, and the player in the field could enter a number to choose whether to pitch to the batter, walk him intentionally, warm up a reliever or change the pitcher. In a later version the options for a pitchout and for a visit to the mound were added.
The player controlling the batter could choose to put in a pinch hitter. If runners were on base the player could direct them to try to steal.
Once the players had entered the desired orders, the game would print out the result of the at-bat, update the number of outs, the score and the location of the runners, and print the name of the next batter.
If a game was still a tie after nine innings, extra innings would be played in accordance with baseball rules. When Daglow ported the game to a batch processing IBM 360 mainframe computer in 1973 this code malfunctioned during testing of the game's card deck and the game continued for thousands of innings, consuming an entire case of printer paper.
A separate version of the game, never distributed by DECUS, simulated the complete 1954 baseball season, printing out the results of each game and the final standings after several hours of computation. A more sophisticated version of the system was used in the first commercial video game to simulate an entire baseball season, Earl Weaver Baseball, designed by Daglow and Eddie Dombrower and published by Electronic Arts in 1987.