The 1939 major league baseball season began on April 17, 1939. The regular season ended on October 1, with the Cincinnati Reds and New York Yankees as the regular season champions of the National League and American League, respectively. The postseason began with Game 1 of the 36th World Series on October 4 and ended with Game 4 on October 8. The Yankees swept the Reds in four games. The Yankees became the first team to win the World Series four years in a row. The seventh Major League Baseball All-Star Game was played on July 11, hosted by the New York Yankees at Yankee Stadium in New York, New York, with the American League winning, 3–1.

Schedule

The 1939 schedule consisted of 154 games for all teams in the American League and National League, each of which had eight teams. Each team was scheduled to play 22 games against the other seven teams of their respective league. This continued the format put in place since the season (except for ) and would be used until in the American League and in the National League. National League Opening Day took place on April 17 with a game between the Pittsburg Pirates and Cincinnati Reds, while American League Opening Day took place on the following day, with a game between the Chicago White Sox and Detroit Tigers. This was the continued the trend since the previous season which saw both leagues opened on different days. It was the first season since that saw both leagues open with just one game each. The final day of the regular season was on October 1 and featured twelve teams. The World Series took place between October 4 and October 8.

Rule change

The 1939 season saw the following rule change:

Teams

An asterisk (*) denotes the ballpark a team played the minority of their home games at

Standings

American League

National League

Postseason

Bracket

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Managerial changes

Off-season

In-season

League leaders

American League

National League

1 National League Triple Crown pitching winner

Awards and honors

Home field attendance

Retired numbers

Events

Deaths