March 6, 1971: Charlie Finley persuaded American League president Joe Cronin to have a preseason game in which a walk was allowed on three pitches rather than four. The Athletics bested the Milwaukee Brewers by a 13–9 tally. Nineteen total walks were issued in the game, and a collective six home runs were hit.
The Cleveland Indians are involved in a bizarre play against the Washington Senators at Robert F. Kennedy Memorial Stadium. The Senators' Tommy McCraw leads off the bottom of the fourth inning with a 140-foot pop fly (some sources say it was 250 feet) into short left-center for what should be an out. Instead, Indians shortstop Jack Heidemann, left fielder John Lowenstein and center fielder Vada Pinson collide into each other going for the ball, which falls amongst the three players. Before the ball can be recovered, McCraw circles the bases for an inside-the-park home run; meanwhile, Heidemann, Lowenstein and Pinson are all injured and have to be replaced. Despite their embarrassing moment, the Indians defeat the Senators 6–3.
June 25 – Willie Stargell of the Pittsburgh Pirates hits what will be the longest home run ever hit at Veterans Stadium. In the second inning of the Pirates' 14–4 victory over the Philadelphia Phillies, his shot off Jim Bunning strikes above an exit in the 600 level in the upper deck. The spot where the ball struck will eventually be marked with a yellow star with a black "S" inside a white circle until Stargell's 2001 death, after which the white circle will then be painted black. The star will remain until the stadium's 2004 demolition.
July 7 – Commissioner Kuhn announces that players from the Negro Leagues elected to the Hall of Fame will be given full membership in the museum. It had been previously announced that they would be honored in a separate wing.
August 28 – Phillies pitcher Rick Wise hits two home runs, including a grand slam off Don McMahon, in the second game of a doubleheader, duplicating his feat in his June no-hitter. Wise beats the Giants 7–3.
November 17 – At age 22, Oakland Athletics pitcher Vida Blue becomes the youngest player ever to win the Most Valuable Player Award and only the fourth to capture both the Cy Young Award and the MVP in the same season.
December 1 – The Chicago Cubs release longtime star and future Hall of Famer Ernie Banks, ending his 19-year major league career. The Cubs also announce that Banks will serve as a coach on manager Leo Durocher's staff in the 1972 season. Mr. Cub finishes his illustrious playing career with 512 home runs and 1,636 RBI.
January 1 – Harry Rice, 69, outfielder noted for his defense who also hit .300 five times
January 7 – Dud Lee, 71, infielder for the St. Louis Browns and Boston Red Sox in the 1920s
January 7 – Hal Rhyne, 71, shortstop who played from 1926 to 1933 for the Pirates, Red Sox and White Sox
January 9 – Elmer Flick, 94, Hall of Fame right fielder and lifetime .313 hitter who led AL in triples three times, steals twice, and batting and runs once each
February 16 – Cedric Durst, 74, outfielder for the St. Louis Browns, New York Yankees, and Boston Red Sox between 1922 and 1930, who also was a member of the 1927 and 1928 World Champions Yankees
February 20 - Vidal López, 52, three-time Triple Crown Pitching winner and slugging outfielder who played in the professional leagues of Cuba, México, Puerto Rico and Venezuela, throughout a career that lasted 21 years between the 1930s and 1950s
March 18 – Tony Welzer, 71, pitcher for the Boston Red Sox from 1926 to 1927, who was the first player born in Germany to appear in an American League game
April 4 – Carl Mays, 79, underhand pitcher who won 20 games five times with three teams, but was best remembered for his pitch which struck Ray Chapman in the head for the only field fatality in major league history
April 9 – Elmer Eggert, 69, pitcher for the 1927 Boston Red Sox
April 9 – Will Harridge, 87, president of the American League from 1931 to 1958
April 15 – Mickey Harris, 54, All-Star pitcher who won 17 games for the 1946 Red Sox, led AL in saves with 1950 Senators
April 16 – William Eckert, 62, commissioner of baseball from 1965 to 1968
April 16 – Ron Northey, 50, outfielder with a powerful arm who hit a record three pinch-hit grand slams in his career
April 19 – Russ Hodges, 60, broadcaster for the Giants since 1949, previously with the Reds, Cubs, Senators and Yankees, best known for his call of Bobby Thomson's pennant-winning home run in 1951
May 12 – Heinie Manush, 69, Hall of Fame left fielder and career .330 hitter who won 1926 batting title with Detroit, led AL in hits and doubles twice each
May 15 – Goose Goslin, 70, Hall of Fame left fielder who starred for five pennant winners in Washington and Detroit, batting .316 lifetime with eleven 100-RBI seasons; one of the first ten players to hit 200 home runs, he retired with the 7th-most RBIs in history
May 20 – Martín Dihigo, 65, Cuban star in the Negro Leagues who excelled at all positions, particularly as a pitcher and second baseman
May 26 – Judge Nagle, 91, pitched for the Pittsburgh Pirates and Boston Red Sox during the 1911 season
July 12 – Wally Judnich, 54, center fielder who twice batted .300 for the St. Louis Browns
July 28 – Myril Hoag, 63, outfielder who recovered from a brutal 1936 collision to become an All-Star three years later
October 8 – Murray Wall, 45, relief pitcher for the Boston Braves, Boston Red Sox and Washington Senators between 1950 and 1959
November 5 – Toothpick Sam Jones, 45, All-Star pitcher who led NL in strikeouts three times after beginning in the Negro Leagues
November 17 – Smead Jolley, 89, outfielder who played for the Chicago White Sox and Boston Red Sox in the 1930s
December 13 – Mike Ryba, 68, pitcher who caught both games of a doubleheader in 1942
December 16 – Ferdie Schupp, 80, pitcher who won 21 games for the 1917 New York Giants but whose career faltered after service in World War I