The 1933 major league baseball season began on April 12, 1933. The regular season ended on October 1, with the New York Giants and Washington Senators as the regular season champions of the National League and American League, respectively. The postseason began with Game 1 of the 30th World Series on October 3 and ended with Game 5 on October 7. In the second iteration of this World Series matchup, the Giants defeated the Senators, four games to one, capturing their fourth championship in franchise history, since their previous in 1922. Going into the season, the defending World Series champions were the New York Yankees from the 1932 season.