Interleague play

Interleague play in Major League Baseball refers to regular-season baseball games played between an American League (AL) team and a National League (NL) team. Interleague play was first introduced in the 1997 Major League Baseball season. Prior to that, matchups between AL teams and NL teams occurred only during spring training, other exhibition games (such as the Hall of Fame Game in Cooperstown, New York), and the World Series. Unlike modern interleague play, none of these contests, except for the World Series, counted toward official team or league records.

Regular season interleague play was discussed for baseball's major leagues as early as 1903, when the two major leagues made peace and formed the National Commission as governing body. The first National Commission Chairman, Cincinnati President Augustus Hermmann, who had already been a proponent of interleague play, proposed an ambitious scheme in late-1904. His plan would've seen the two leagues' ending their seasons earlier, after approximately 116 games, "and then have every National League team play two games in every American League city, and have every American League team play two games in every National League city." Another interleague play idea was floated around the same time by Boston Americans owner John Taylor, whose plan was for each league to play its full 154-game schedule, to be followed by not just a championship series between the two league winners, but also by series' between the two second-place finishers, the two third-place teams, and all other corresponding finishers.

In August 1933, several owners reacted favorably to a proposal by Cubs' President William L. Veeck to have teams play four interleague games in the middle of the season, beginning in 1934. In December 1956, Major League owners considered a proposal by Cleveland general manager and minority-owner Hank Greenberg to implement limited interleague play beginning in 1958. Under Greenberg's proposal, each team would continue to play a 154-game season, with 126 within that team's league, and 28 against the eight clubs in the other league. The interleague games would be played immediately following the All-Star Game. Notably, under Greenberg's proposal, all results would count in regular season game standings and league statistics. While this proposal was not adopted, the current system shares many elements. Bill Veeck predicted in 1963 that Major League Baseball would someday have interleague play. While the concept was again considered in the 1970s, it was not implemented until the 1990s, at least in part as an effort to renew the public's interest in MLB following the 1994 players' strike.

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