1903 Major League Baseball season
| 1903 MLB season | |
|---|---|
| League | American League (AL) National League (NL) |
| Sport | Baseball |
| Duration | Regular season:
|
| Number of games | 140 |
| Number of teams | 16 (8 per league) |
| Pennant winners | |
| AL champions | Boston Americans |
| AL runners-up | Philadelphia Athletics |
| NL champions | Pittsburgh Pirates |
| NL runners-up | New York Giants |
| World Series | |
| Champions | Boston Americans |
| Runners-up | Pittsburgh Pirates |
The 1903 major league baseball season began on April 16, 1903. The regular season ended on September 29, with the Pittsburgh Pirates and the Boston Americans as regular season champions of the National League and American League, respectively. The postseason began with Game 1 of the first modern World Series on October 1 and ended with Game 8 on October 13. The Americans defeated the Pirates, five games to three, capturing their first championship in franchise history.
The 1903 season saw the return of a postseason championship series, the World Series, following the one-off 1900 Chronicle-Telegraph Cup. It was also the first inter-league series since the 1890 World's Championship Series between the National League and defunct-since-1891 American Association. The 1903 World Series would also mark the first championship series that is still celebrated today, as all previous series are considered pre-modern and these early contests are discussed by MLB and baseball historians separately.
The defunct Baltimore Orioles were replaced by a new franchise in New York City known as the New York Highlanders; it was the last change to the lineup of AL and NL franchises until 1953. The American League would not return to Baltimore until the St. Louis Browns relocated their as a new Baltimore Orioles in 1954. The Chicago Orphans and Cleveland Bronchos were renamed as the Chicago Cubs and Cleveland Naps, respectively.