1908 Major League Baseball season

The 1908 major league baseball season began on April 14, 1908. The regular season ended on October 8, with the Chicago Cubs and Detroit Tigers as regular season champions of the National League and American League, respectively. In a rematch of the prior year's postseason, the postseason began with Game 1 of the fifth modern World Series on October 10 and ended with Game 5 on October 14. The Cubs defeated the Tigers, four games to one.

The Boston Americans renamed as the Boston Red Sox.

Schedule
The 1908 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 for the season. This format would last until.

Opening Day took place on April 14 with all but the Pittsburgh Pirates and St. Louis Cardinals playing. The final day of the regular season was on October 8. The World Series took place between October 10 and October 14.

Rule changes
On February 27, 1908, the three organizations of the National Commission of Baseball Clubs, National League, and American League announced several rule changes, effective immediately.
 * The act of rubbing the ball on the ground, clothing, shoes, or dropping the ball and picking it up with a handful of gravel or dirt by the pitcher was prohibited.
 * The sacrifice fly rule is adopted. No time at bat is charged if a run scores after the catch of a fly ball. The rule would eventually be repealed in 1931, then reinstated (or changed) several times before gaining permanent acceptance in 1954.
 * The trend of each team playing 22 games with every other in-league team was written into the Major League Baseball Constitution, with rules for playing makeup games at the originally scheduled ballpark in the event of tie games, rain delays, and other game-preventing situations being put in place. If the series of all scheduled games has ended with makeup games remaining, if possible, the remaining game(s) can be made up on the opposite team's ballpark, with a date agreed by the two teams.

Bracket
 

National League
1 National League Triple Crown pitching winner

Events

 * June 30 – Cy Young pitches the third, and final, no-hitter of his career as the Boston Red Sox defeat the New York Highlanders, 8–0.
 * July 4 – One batter away from a perfect game, New York Giants pitcher Hooks Wiltse hits George McQuillan with two outs in the ninth inning. Wiltse continues to pitch and tosses a no-hitter against the Philadelphia Phillies. The Giants win, 1–0, in 10 innings.
 * August 4 – In a game between the St. Louis Cardinals and the Brooklyn Superbas only one baseball was used for the entire game. Brooklyn wins, 3–0.
 * September 5 – Nap Rucker pitches a no-hitter as the Brooklyn Superbas defeat the Boston Doves, 6–0.
 * September 18 – Cleveland Naps pitcher Bob Rhoads tosses a no-hitter against the Boston Red Sox, Cleveland wins, 2–1.
 * September 20 – Frank Smith of the Chicago White Sox throws a no-hitter against the Philadelphia Athletics, the White Sox win, 1–0. It is the second no-hitter of Smith's career.
 * September 23 – The Chicago Cubs and New York Giants, involved in a tight pennant race, (also involving the Pittsburgh Pirates) were tied in the bottom of the ninth inning at the Polo Grounds in New York. The Giants had runners on first and third and two outs when Al Bridwell hit a single to center field, scoring Moose McCormick from third with the Giants' apparent winning run, but the runner on first base, rookie Fred Merkle, thinking the game was over, went halfway to second and then sprinted to the clubhouse after McCormick touched home plate. As fans swarmed the field, Cub infielder Johnny Evers retrieved the ball and touched second. A forceout was called at second base, nullifying the single, and because there were 2 outs when the play started, the run was also nullified and the inning ended. The game was declared a tie and would be made up at the end of the season if the Cubs and Giants were tied for first place. The incident became known as the "Merkle Boner".
 * September 26 – Ed Reulbach of the Chicago Cubs pitches two shutouts in a doubleheader against the Brooklyn Superbas, winning both games 5–0 and 3–0.
 * October 2 – In a game involving the Cleveland Naps and the Chicago White Sox, Ed Walsh struck out 15 Naps and walked one batter, pitching a complete game, but it was not enough as Addie Joss pitched a perfect game, and the Naps beat the White Sox, 1–0, during the heat of a pennant race. Cleveland center fielder Joe Birmingham scored the game's only run. It is perhaps the finest pitching duel in baseball history.
 * October 6 – The Detroit Tigers defeat the Chicago White Sox, 7–0, to win the American League pennant on the last day of the season.
 * October 8 – The Chicago Cubs defeat the New York Giants, 4–2, in the make-up of the "Merkle Boner" game, giving the Cubs the National League pennant.
 * October 14 – The Chicago Cubs defeat the Detroit Tigers, 2–0, in Game 5 of the World Series to win the series four games to one. It is the second consecutive World Championship for the Cubs and the second year in a row they defeated the Tigers in the World Series. The Cubs would not win another World Series until 2016.
 * The St. Louis Cardinals set a Major League record which stills stands for the fewest runs scored in a full season, with only 372.