July 6 – Jocko Conlan makes his major league debut in right field for the Chicago White Sox. After two seasons as a part-time player with the ChiSox, Conlan retires in order to pursue a career as an umpire.
August 14 – The Detroit Tigers sweep the New York Yankees in a double header to bring their winning streak to fourteen games. The Yankees beat them the following day to end the streak.
September 16 – In the first game of a double header with the Brooklyn Dodgers, Phil Cavarretta makes his major league debut for the Chicago Cubs at barely eighteen years old. He strikes out in one at-bat as a pinch hitter.
September 23 – With a 2½ games lead in the National League, the New York Giants lose the second game of a double header to the Boston Braves. The Giants lose their last five games of the season, to end two games back of the St. Louis Cardinals, who win their last four.
September 26 – The Detroit Tigers sweep a double header from the Chicago White Sox, giving Chicago ten losses in a row, and 97 losses for the season. The ChiSox, however, go 2-2 in their final four games to avoid 100 losses for the season.
October 3 – Sloppy play by the Detroit Tigers (five errors) helps the Cardinals cruise to an 8-3 victory in game one of the 1934 World Series.
October 4 – Goose Goslin's single in the twelfth wins it, as the Tigers take game two, 3-2.
October 5 – With two outs in the ninth inning, Paul Dean allows the Detroit Tigers their only run of the game. The Cards take a 2-1 series advantage with both wins come with one of the Dean brothers on the mound.
October 6 – This time it is the Cardinals who commit five errors in one game, two of which came in the Tigers' five run eighth inning, as Detroit wins game four, 10-4.
October 7 – The Detroit Tigers take game five of the World Series, 3-1. Dizzy Dean in the losing pitcher.
October 8 – Daffy Dean pitches nine innings, and again just gives up one earned run. Sloppy play, however, allows the Tigers to plate two more. Dean helps his own cause with a single in the seventh to drive in the game-winning run as the Cardinals win 4-3 to even up the series.
October 9 – The St. Louis Cardinals defeat the Detroit Tigers, 11–0, in Game seven of the World Series to win their third World Championship, four games to three. All four games are won by one of the Dean brothers (Dizzy is 2-1, Paul is 2-0). The St. Louis "Gashouse Gang" collected 73 hits in the series.
December 26 – Matsutaro Shoriki, head of Yomiuri Shimbun, announces the formation of the first professional baseball team in Japan, the Yomiuri Giants. The team is composed primarily of players who had played the American All-Stars who had toured Japan.
January 9 – Perry Werden, 68, first baseman who played for the St. Louis Maroons, Washington Nationals, Toledo Maumees, Baltimore Orioles, St. Louis Browns and Louisville Colonels in parts of seven seasons spanning 1884–1897.
January 16 – Wiley Dunham, 56, pitcher for the 1902 St. Louis Cardinals.
January 16 – Jim Hyndman, 67, Canadian pitcher and outfielder who played for the Philadelphia Athletics in the 1886 season.
January 24 – Harry Hogan, 57, backup outfielder who appeared in one game for the Cleveland Blues during the 1901 season.
January 28 – John Kane, 51, outfielder who played with the Cincinnati Reds in 1907 and the Chicago Cubs in 1910.
January 29 – Bill Schenck, 79, infielder who played for the Louisville Eclipse, Richmond Virginians and Brooklyn Grays in a span of three seasons from 1882–1885.
January 30 – Frank McGee, 34, first baseman who played two games for the 1925 Washington Senators.
February 8 – Tom Sexton, 68, shortstop for the 1884 Milwaukee Brewers.
February 12 – Rowdy Elliott, 43, catcher who spent 23 years in baseball between 1907 and 1929, which included stints in the majors with the Boston Doves (1910), Chicago Cubs (1916–1918) and Brooklyn Robins (1920), being also a World War I veteran.
February 20 – George Mappes, 68, backup catcher and second baseman who played from 1885 to 1886 for the Baltimore Orioles and the St. Louis Maroons.
February 21 – Doc Adkins, 61, pitcher who played with the Boston Americans in 1902 and the New York Highlanders in 1903.
February 21 – Jim Roxburgh, 76, catcher for the 1884 Baltimore Orioles and the 1887 Philadelphia Athletics.
February 25 – John McGraw, 60, Hall of Fame manager who from 1902 through 1932 led the New York Giants to three World Series championships, 10 National League pennants, and 21 first-or second-place finishes, whose 2,763 managerial victories rank him second only to Connie Mack's career-best total of 3,731.
February 27 – Frank Shannon, 60, shortstop who played with the Washington Senators in 1892 and the Louisville Colonels in 1896.
February 28 – John Irwin, 72, third baseman who played for the Worcester Ruby Legs, Boston Reds, Philadelphia Athletics, Washington Nationals, Buffalo Bisons, Boston Reds and Louisville Colonels in parts of eight seasons spanning 1882–1891.
March 3 – Mike O'Rourke, 65, pitcher for the Baltimore Orioles during the 1890 season.
March 7 – Bill Rotes, 62, pitcher for the Louisville Colonels in 1893.
March 9 – Dan Dugdale, 69, catcher who played with the Kansas City Cowboys in 1886 and the Washington Senators in 1894.
March 13 – Fielder Jones, 62, center fielder and manager who guided the Brooklyn Superbas to two National League titles from 1899 to 1900, and the Chicago White Sox to the 1901 American League title and the 1906 World Series championship, while batting over .300 in six seasons and collecting 683 victories as a manager.
March 16 – Adrian Lynch, 37, pitcher for the St. Louis Browns in the 1920 season.
March 19 – Ray Jansen, 45, third baseman who played with the St. Louis Browns in 1910.
March 20 – Herm Doscher, 81, third baseman for five teams between 1872 and 1882, who also umpired during five seasons in the National League and the American Association.
March 21 – Pea Ridge Day, 34, pitcher who played from 1924 through 1931 for the St. Louis Cardinals and the Cincinnati Reds, and with the Brooklyn Robins in the 1931 season.
March 28 – Ed Larkin, 48, catcher for the 1909 Philadelphia Athletics.
April 1 – Barney Gilligan, 78, catcher who played from 1879 through 1888 for the Cleveland Blues, Providence Grays, Washington Nationals and Detroit Wolverines.
April 2 – John Roach, 66, pitcher for the 1887 New York Giants.
April 4 – Dick Johnston, 70, center fielder who played eight seasons from 1884 to 1891, while appearing for five different teams in three different leagues, which included stints with the Richmond Virginians, Boston Beaneaters, Boston Reds, New York Giants and Cincinnati Kelly's Killers.
April 10 – Bill Hunter, 46, outfielder who played with the Cleveland Naps in the 1912 season.
April 11 – Charles Moran, 55, backup infielder who played from 1903 through 1905 for the Washington Senators and St. Louis Browns.
April 19 – Charlie Hickman, 57, valuable utility and smart bases runner who played for nine different clubs in the American and National leagues from 1897 to 1908, amassing 91 career triples and several inside-the-park home runs, while leading the AL with 193 hits and 288 total bases in the 1902 season.
April 22 – Gus Creely, 63, shortstop who played for the St. Louis Browns during the 1890 season.
April 27 – Joe Vila, 67, journalist and editor for Boston and New York newspapers, who has been regarded as one of the most influential sportswriters during the first third of the 20th century, while setting fundamental changes in sports coverage during the decades to come.
May 3 – Lew Graulich, 72, catcher/first baseman for the 1891 Philadelphia Phillies.
May 10 – Ed Willett, 50, pitcher for the Detroit Tigers from 1906 through 1913, who posted a 21-10 record and a 2.34 ERA to lead Detroit to the 1909 American League pennant, pitching later for the St. Louis Terriers of the outlaw Federal League in 1914 and 1915.
May 14 – Lou Criger, 62, the first Opening Day catcher in Boston American League franchise's history, who was behind plate for most of Cy Young's 511 victories, and also caught every inning of eight games in the first-ever World Series in 1903, helping Boston win the championship.
May 18 – Jumbo McGinnis, 80, ace pitcher for the original St. Louis Brown Stockings from 1882 to 1886, who hurled for them over 350 innings and averaged 26 wins in three consecutives seasons, while leading the American Association with six shutouts in 1883.
June 2 – James Pirie, 81, shortstop for the 1883 Philadelphia Quakers.
June 9 – Charlie Dexter, 57, catcher who played from 1896 through 1903 for the Louisville Colonels, Chicago Orphans and Boston Beaneaters.
June 10 – Les German, 65, pitcher who played with the Baltimore Orioles, New York Giants and Washington Senators, in all or part of six seasons spanning 1890–1896.
June 11 – Tim Manning, 80, second baseman who played for the Providence Grays and the Baltimore Orioles from 1882 to 1885.
June 21 – Monte Cross, 64, slick shortstop and speedy base runner during 15 seasons for five different franchises in the National and American leagues between 1892 and 1907, who played mostly for the Philadelphia Athletics and Phillies clubs from 1897 through 1907, earning six titles in putouts and three in assists while amassing a career 328 stolen bases.
June 29 – Charles Somers, 65, founding member of the American League in 1901 and also its principal financier, who owned the Cleveland Indians and also helped the junior circuit establish clubs in the cities of Boston, Chicago and Philadelphia.
July 6 – Ray Francis, 42, who pitched for the 1922 Washington Senators and the 1923 Detroit Tigers, and for the New York Yankees and Boston Red Sox in the 1925 season.
July 18 – Sy Sanborn, 67, sportswriter for the Chicago Tribune from 1900 to 1920 and one of the founding members of the Baseball Writers' Association of America in 1908, who later collaborated for several years for The Sporting News.
July 19 – Ed Hutchinson, 67, second baseman for the Chicago Colts in the 1890 season.
July 29 – Walt McCredie, 57, outfielder for the 1903 Brooklyn Superbas of the National League, who later played and managed in the minor leagues for many years, leading his Portland team to Pacific Coast League pennants in 1906, 1910, 1911, 1913, and 1914.
July 29 – Dan Phelan, 81, first baseman who played for the Louisville Colonels of the American Association in 1890.
August 2 – Reggie Richter, 45, German pitcher for the Chicago Cubs in the 1911 season, who also spent four seasons in the minors with the Louisville Colonels, Montreal Royals and Newark Indians.
August 3 – Charlie Hastings, 63, pitcher for the Cleveland Spiders in 1893 and the Pittsburgh Pirates from 1896 through 1898.
August 8 – Wilbert Robinson, 70, Hall of Fame player and manager who spent 35 years in the majors, first as an outstanding catcher for the Baltimore Orioles during the 1890s, and later managing the Brooklyn Robins to two National League pennants in 1916 and 1920, while compiling a 1,399–1,398 managing record from 1914 to 1931.
August 11 – Joe Ward, 49, backup infielder who played with the Philadelphia Phillies in 1906, and for the New York Highlanders and the Philadelphia Phillies from 1909 to 1910.
August 12 – Ed Andrews, 75, outfielder and second baseman for the Philadelphia Quakers, Indianapolis Hoosiers, Brooklyn Ward's Wonders and Cincinnati Kelly's Killers in parts of nine seasons spanning 1884–1891, who led the National League with 56 stolen bases in 1896, and topped American Association outfielders with a .961 fielding average in 1891.
August 14 – Guy Morrison, 38, pitcher for the Boston Braves in the 1927 and 1928 seasons.
August 17 – Doc Potts, 65, catcher who appeared in one game for the 1892 Washington Senators of the National League.
August 21 – Carl Lundgren, 54, pitcher who posted a 91-55 record and a 2.42 ERA in 178 games for the Chicago Cubs, while helping his team win three consecutive National League pennants from 1906 to 1908, and two World Series championships in 1907 and 1908.
August 26 – Bill Kling, 67, pitcher who played from 1891 through 1892 for the Philadelphia Phillies and Baltimore Orioles, and with the Louisville Colonels in 1895.
August 27 – Henry Kohler, 82, National Association catcher/infielder for the Fort Wayne Kekiongas in 1871, and the Baltimore Marylands/Canaries from 1873 to 1874.
October 4 – Nixey Callahan, 60, one of the most versatile figures in the late 1800s and early 1900s, who averaged 16 wins in six full seasons, including two 20-wins seasons in 1903–1904 and the first no-hitter in American League history in 1902, while also playing the outfield and four infield positions between pitching appearances, to later manage the Chicago White Sox and the Pittsburgh Pirates.
October 6 – Tom Mansell, 79, outfielder who played for the Troy Trojans, Syracuse Stars, Detroit Wolverines, St. Louis Browns, Cincinnati Red Stockings and Columbus Buckeyes in parts of three seasons spanning 1879–1884.
October 8 – Bill Snyder, 36, pitcher for the Washington Senators from 1919 to 1920.
October 9 – Pat Pettee, 71, second baseman who played for the Louisville Colonels in 1891.
October 11 – Sandy Burk, 47, pitcher who played for the Brooklyn Superbas, Brooklyn Dodgers, St. Louis Cardinals and Pittsburgh Rebels in a span of five seasons from 1910–1915.
October 14 – Les Cox, 30, pitcher for the 1926 Chicago White Sox.
October 16 – Highball Wilson, 56, pitcher who played for the Cleveland Spiders in 1899, the Philadelphia Athletics in 1902, and the Washington Senators from 1903 to 1904.
October 18 – Guy Morton, 41, pitcher for the Cleveland Naps and Cleveland Indians from 1914 to 1924.
October 20 – Paddy Greene, 59, third baseman who played from 1902 through 1903 for the Philadelphia Phillies, New York Highlanders and Detroit Tigers.
October 22 – Belden Hill, 70, third baseman for the 1890 Baltimore Orioles of the American Association.