The regular season ended on October 3, with the New York Giants and New York Yankees as the regular season champions of the National League and American League, respectively.
The Giants defeated the Brooklyn Dodgers in a regular season best-of-three tiebreaker, for the National League title, after both teams finished their 154-game schedules with identical 96–58 records.
After splitting the first two games, the stage was set for a decisive third game, won in dramatic fashion on a walk-off home run from the bat of Giant Bobby Thomson, one of the most famous moments in the history of baseball, commemorated as the "Shot Heard 'Round the World" and "The Miracle at Coogan's Bluff".
On May 1, the Chicago White Sox become the sixth team in professional baseball to break the color line when they fielded future Hall-of-Famer Minnie Miñoso.
The final day of the scheduled regular season was on September 30, which saw all sixteen teams play, continuing the trend from 1946.