*Ty Cobb of the Detroit Tigers hits his first career grand slam. After six innings, Detroit leads the Boston Red Sox, 10–1. Nevertheless, Boston comes back to win the game 13–11 in 10 innings.
*The New York Giants score a Major League record 10 runs before the St. Louis Cardinals retire the first batter in the first inning. Fred Merkledrives in six of the Giants' 13 runs in the first en route to a 19–5 victory. When Giants manager John McGraw decides to save starting pitcherChristy Mathewson for another day, Rube Marquard enters the game in the second inning and sets a record for relievers with 14 strikeouts in his eight-inning relief appearance.
May 14 – In their first Sunday home game, the Cleveland Naps defeat the New York Highlanders, 16-3, before a crowd of nearly 16,000 spectators. Cleveland's George Stovall leads the offense with 4 hits.
June 18 – The Detroit Tigers staged the biggest comeback in Major League history after overcoming a 13-1 deficit to defeat the Chicago White Sox by a score of 16–15.
July 19 – former circus acrobat Walter Carlisle completed an unassisted triple play for the Vernon Tigers of the Pacific Coast League. With the score tied at 3–3 in the sixth inning, and men on first and second base, Carlisle made a spectacular diving catch of a short fly by batter Roy Akin; stepped on second to retire Charlie Moore, and tagged George Metzger coming from first. The Tigers won the game, 5–4. With his heroic feat, the speedy English-born Carlisle entered the records books as the only outfielder ever to make an unassisted triple play in organized baseball.
June 28 – The new Polo Grounds, a horseshoe-shaped structure, opens.
July 29 – In the first game of a doubleheader, Smoky Joe Wood pitches a no-hitter against the St. Louis Browns in a 5-0 Boston Red Sox victory.
August 27 – Ed Walsh of the Chicago White Sox pitches a 5–0 no-hitter against the Boston Red Sox.
September 12 – In the nightcap of a game billed as a pitchers' duel, Boston Rustlers' Cy Young and the New York Giants' Christy Mathewson face each other before 10,000 fans, Boston's largest crowd of the year. Young gives up three home runs and nine runs in less than three innings. After the Giants build a 9–0 lead, Giants' manager John McGraw lifts Mathewson, who pitched just two innings, preferring to save his ace for the pennant race against the Chicago Cubs and the Philadelphia Phillies. This is the only time the two future Hall of Fame pitchers ever face each other.
October 22 – The World Series between the New York Giants and the Philadelphia Athletics was resumed after six days of rain, and Chief Bender beat Christy Mathewson, 4–2, to give the Athletics a 3-1 lead.
October 26 – The Philadelphia Athletics defeat the New York Giants, 13–2, in Game 6 of the World Series to win their second consecutive World Championship title. Philadelphia wins the series, four games to two. The six consecutive days of rain between Games 3 and 4 caused the longest delay between World Series games until the Loma Prieta earthquake interrupted the 1989 Series, which incidentally featured the same two franchises, albeit on the west coast.
December 1 – Future Hall of Fame member Walter Alston is born in Venice, Ohio. Although Alston will come to bat only once during a brief major league career, he will have far greater longevity as the manager of the Dodgers from to.
November 10 – Clark Griffith becomes a club owner and president when he joins Philadelphia grain broker William Richardson in buying controlling interest in the Washington Senators for $175,000. Griffith, unable to get financial help from the American League, mortgages his ranch in Montana to raise funds.
March 10 – Guy McFadden, 38, first baseman for the 1895 St. Louis Browns of the National League.
March 12 – Simon Nicholls, 28, shortstop for the Detroit Tigers, Philadelphia Athletics and Cleveland Naps between the 1906 and 1909 seasons.
April–June
April 5 – Frank Hankinson, 54, third baseman and pitcher who played from 1878 through 1888 with the White Stockings, Blues, Trojans, Gothams. Metropolitan and Cowboys.
April 14 – Addie Joss, 31, pitcher for Cleveland who won 20 games four times, led American League in ERA twice with a career 1.89 ERA, including one-hitter in major league debut, one no-hitter and a perfect game.
April 23 – George Craig, 23, pitcher for the 1907 Philadelphia Athletics.
April 25 – Jack Rowe, 54, catcher and shortstop for Buffalo and Detroit who batted.300 four times, led NL in triples in 1881; did not strike out in entire 1882 season, later a minor league manager
May 26 – Billy O'Brien, 51, third baseman for four teams in two different leagues from 1884 to 1890, who topped the Nationel League batters with 19 home runs in 1887.
June 3 – Dad Clarke, 46, who pitched from 1888 to 1898 for the White Stockings/Solons/Giants/Colonels, going 44-51 with a 4.17 ERA.
July 26 – John Radcliff, 65, shortstop for five seasons in the National Association.
August 5 – Bob Caruthers, 47, pitcher who compiled the highest career winning percentage among major leaguers with 250 decisions; led American Association with 40 victories in both 1885 and 1889, pacing St. Louis and Brooklyn to respective pennants; batted.300 twice, later an umpire
August 8 – Joe Walsh, 46, infielder for the 1881 Baltimore Orioles of the American Association.
August 31 – Will White, 56, pitcher who won over 200 games for Cincinnati teams in 10-year career, led league in wins and strikeouts twice each; first major leaguer to wear eyeglasses, and batterymate of brother Deacon from 1877–79
September–December
October 1 – Leo Hafford, 28, pitcher for the 1906 Cincinnati Reds.
October 6 – Larry Murphy, 54, Canadian outfielder for the 1891 for the Washington Statesmen.
October 10 – Bill Parks, 62, pitcher and left fielder for three teams from 1875 to 1876. Managed the 1875 Washington Nationals for eight games in 1875.
October 19 – Marshall King, 61, outfielder who played from 1867 to 1872 for the Haymakers, White Stockings and Haymakers.
October 25 – Chris Rickley, 52, shortstop for the 1884 for the Philadelphia Keystones of the Union Association.
November 4 – Warren Burtis, 63, National League umpire in 1876 and 1877.
November 8 – Oscar Bielaski, 64, right fielder for five seasons, from 1872 to 1876, who was on the 1876 National League champion Chicago White Stockings.
November 8 – Frank Gatins, 40, infielder for the Washington Senators and Brooklyn Superbas.
November 22 – Ed Cermak, 30, outfielder for the 1901 Cleveland Blues of the American League.
November 6 – John Hamill, 40, pitcher for the 1884 Washington Nationals.
December 6 – Ed Glenn, 36, National League shortstop who played between 1898 and 1902 with the Washington Senators, New York Giants and Chicago Orphans.
December 31 – Pete Gilbert, 43, third baseman for the Orioles/Grooms/Colonels American Association teams from 1890 to 1894.