February 12 - Minor league outfielder Gordon Houston becomes the first player in Organized Baseball to die during active duty in World War II. Houston had played with Texarkana in 1940.
March 18 - Jackie Robinson and Nate Moreland request try-outs with the White Sox. Sox manager Jimmie Dykes praises Robinson's baserunning to Pittsburgh Courier sportswriter Herman Hill, saying that "he stole everything but my infielders' gloves." Dykes goes on record to the Courier, saying "Personally, I would welcome Negro players on the White Sox and I believe every one of the other fifteen managers would do so likewise. As for the players, they'd all get along too." Ultimately, Dykes is unable to even consider offering contracts to either, stating that it is a matter for club owners, league officials, and the Commissioner of Baseball to allow it.
May 13 - Jim Tobin of the Boston Braves almost single-handedly beats the Chicago Cubs at Braves Field, 6–5, by pitching a five-hitter and hitting three consecutive home runs. Tobin, who hit a pinch-homer the day before, becomes the only pitcher in modern history to collect three home runs in a Major League game. His fourth at-bat results in a fly ball caught against the fence in left field.
August 23 - Babe Ruth dons a uniform for the first time in 7 years for a hitting exhibition against Walter Johnson at Yankee Stadium. On Johnson's fifth pitch, Ruth hit a drive into the lower right field stands as the crowd thundered its approval. On the final pitch, Ruth hit a towering upper-deck shot that was just foul. He circled the bases doffing his cap and saluting the roaring crowd with every step. Ruth and Johnson then left the field together to a thunderous ovation. $80,000 was raised for the Army-Navy relief fund.
September 11 - Chicago CubscatcherPaul Gillespie homers in his first major league at bat. In 1945 he will homer in his final major league at bat and become the only player in MLB history to do both.
September 27 - The St. Louis Cardinals clinch the National League pennant on the last day of the regular season by defeating the Chicago Cubs, 9-2, in the first game of a double header at Sportsman's Park, St. Louis. The Cardinals also win Game 2 of the double header and finish the season with a record of 106-48, giving them the most victories by any National League team since Pittsburgh's 110 wins in 1909. Meanwhile, the Brooklyn Dodgers win their season finale, 4-3, against Philadelphia to end the season in second place at 104-50.
December 1 - At major league meetings in Chicago, World War II travel restrictions are the order of the day. Owners decide to restrict travel to a three-trip schedule rather than the customary four. Spring training in 1943 will be limited to locations north of the Potomac or Ohio rivers and east of the Mississippi.
January 4 – Herold Juul, 48, pitcher for the 1914 Brooklyn Tip-Tops of the Federal League.
January 8 – Harry Pearce, 52, second baseman who played from 1917 through 1919 for the Philadelphia Phillies.
January 22 – Louis Santop, 52, Hall of Fame catcher in the Negro Leagues, an amazing .406 lifetime hitter and the first legitimate home run slugger in black baseball history.
January 31 – Henry Larkin, 19th century first baseman and manager who hit .303 in 10 seasons with the Philadelphia Athletics, Cleveland Infants/Indians and Washington Senators.
January 31 – Ed Phelps, 62, catcher who played with four teams in 11 seasons spanning 1902–1913, and a member of the Pittsburgh Pirates teams who the 1902 and 1903 National League Pennants and played in the 1903 World Series.
May 28 – Charley Bassett, 79, infielder for five National League teams in a span of eight seasons from 1884–1892, who led the league's second basemen in assists in 1887, and fielding percentage in 1887 and 1890.
July 1 – Harry Spies, 76, first baseman and catcher who played for the Louisville Colonels and Cincinnati Reds during the 1895 season.
July 17 – Lefty Johnson, 79, outfielder for the Philadelphia Keystones, Indianapolis Hoosiers and Baltimore Orioles in parts of five seasons from 1884–1892.
July 20 – Rap Dixon, 39, All-Star outfielder in the Negro Leagues from 1922 through 1937; a power hitter who could also hit for average as well as one of the fastest players and best defensive outfielders in Negro League history.
July 30 – Jim Baskette, 54, pitcher for the Cleveland Naps from 1911 until 1913.
December 5 – Val Picinich, 46, catcher in 1307 games for the Philadelphia Athletics, Washington Senators, Boston Red Sox, Cincinnati Reds, Brooklyn Robins/Dodgers and Pittsburgh Pirates between 1916 and 1933.
December 6 – Amos Rusie, 71, Hall of Fame fireball pitcher whose powerful delivery was the main reason to move the pitching mound in 1893 from 50 feet to its present 60 feet, 6 inches; who retired with a 246-174 record, 1,950 strikeouts and 3.07 ERA in what was really an eight-year career with the New York Giants, collecting 30 or more wins four years years in a row and winning 20 or more games eight successive times, while leading the National League in strikeouts five years and leading or tying for most shutouts five times, including a no-hitter, and the Triple Crown in 1894 with a 36-13 mark, 195 strikeouts and a 2.78 ERA en route to a 4–0 four-game sweep of the Baltimore Orioles in the first Temple Cup Championship Series.