February 3 – The Hall of Fame's Special Committee on the Negro Leagues picks versatile Cuban star Martín Dihigo and shortstop John Henry Lloyd for induction. The committee then dissolves, its functions being taken over by the Veterans Committee.
March 21 – Mark Fidrych, the 1976 AL Rookie of the Year, rips the cartilage in his left knee and will undergo surgery in ten days. The injury will effectively end the career of The Bird.
March 28 – While in Orlando, Florida for an exhibition game with the Minnesota Twins, the Texas Rangers' Lenny Randle walks up to Rangers manager Frank Lucchesi during batting practice and says he wanted to talk to him. Words are exchanged, and Randle punches Lucchesi, who was still in street clothes, in the face. Lucchesi is hospitalized for a week, needing plastic surgery to repair his fractured cheekbone which Randle breaks in three places. He also receives bruises to his kidney and back. The Rangers suspend Randle for 30 days without pay and fined him $10,000. Randle is charged with assault, and would plead no contest to battery charges in a Florida court, getting slapped with a $1,050 fine.
April 24 – Canadian Ferguson Jenkins throws the first shutout ever in Exhibition Stadium, as the visiting Boston Red Sox defeat the Toronto Blue Jays 9-0.
April 26 – Before completing his suspension with the Texas Rangers, Lenny Randle is traded to the New York Mets for a player to be named later.
May 11 – Atlanta Braves owner Ted Turner names himself manager, and manages the Braves to a loss. He is ordered by National League president Chub Feeney to desist, and soon after, owners are banned from managing.
June 18 – In the sixth inning of an NBC-televised game against the Boston Red Sox at Fenway Park, New York Yankees manager Billy Martin pulls right fielder Reggie Jackson and replaces him with Paul Blair after Jackson misplays Jim Rice's fly ball for a double. As Jackson returns to the dugout, he and Martin exchange words, Martin arguing that Jackson had shown him up by "not hustling" on the play. The Yankee manager lunges at Jackson (who is 18 years younger than Martin and outweighs him by about 40 pounds), and has to be restrained by coaches Yogi Berra and Elston Howard—with the NBC cameras showing the confrontation to the entire country. The Red Sox win, 10-4.
June 21 – Frank Lucchesi is fired as manager of the Texas Rangers with a 31-31 record following a 9-5 loss to the Minnesota Twins. Lucchesi blames former Ranger Lenny Randle, with whom he got into a confrontation during Spring training, for the firing, and sues him for $200,000.
June 22 -- Eddie Stanky replaces Lucchesi as Rangers manager. He wins the game, and then surprisingly resigns as manager a mere 18 hours after being hired, one of the shortest tenures in MLB history.
June 27 – The San Francisco Giants' Willie McCovey smashes two home runs, one a grand slam off reliever Joe Hoerner, in the sixth inning to pace a 14–9 victory over the Cincinnati Reds. McCovey becomes the first player in major league history to twice hit two home runs in one inning (his first time was on April 12, 1973), and also becomes the all-time National League leader with 17 career grand slams. Andre Dawson, in both 1978 and 1986, will be the next player to hit two homers in the same inning.
July 13 – The New York Mets trailed the Chicago Cubs 2-1 in the sixth inning when the lights went out as New York City is stricken with a blackout that would last two days. The game was resumed on September 16, with the Cubs winning 5-2.
For the first time since 1906 both Chicago teams were in first place at the All-Star break. However the Cubs, who had a 47-22 won-lost record at one point, skidded during the second half of the season to a mediocre 81-81 won-lost record while the Chicago White Sox, although succeeding in winning 90 games, were quickly overwhelmed by the run-away AL West Division winner Kansas City Royals in September.
August 7 – In the second game of a doubleheader at Wrigley Field, Mick Kelleher of the Chicago Cubs and Dave Kingman the San Diego Padres are involved in a bench-clearing brawl—a melee with a rare mismatch between the two major combatants. The 6-6, 210-pound Kingman, apparently angered over being hit by a Steve Renko pitch leading off the second inning, responds by sliding hard into Kelleher, the Cubs' 5-9, 170-pound second baseman, on George Hendrick's ground ball one batter later. Kelleher responds by jumping onto Kingman's back and pummeling him with blows. Both Kelleher and Kingman are ejected from the game, which the Cubs win 9-4.
August 17 – Records fall as the Mexican League concludes its season. Ironman reliever Aurelio López of the Mexico City Reds racks up his 30th save to go with a record 19 victories in relief. Veteran Tampico first baseman Héctor Espino hits 14 home runs, raising his career total to 435, a new minor league record. Thirty-eight-year-old Vic Davalillo, the league's top hitter with a .384 batting average, is purchased by the Los Angeles Dodgers.
August 31 – Hank Aaron's major league mark of 755 career home runs is tied by Sadaharu Oh in Japan. Three days later, Oh will hit his 756th homer to surpass Aaron's total, becoming the most prolific home run hitter in professional baseball history.
September 3 – Sadaharu Oh surpassed Hank Aaron's world record of home runs hit when he hit home run #756.
September 9 – In the second game of a double header in Boston, the Detroit Tigers debut their new second baseman, Lou Whitaker, and their new shortstop, Alan Trammell. They will play side by side for 19 years to establish a new Major League record for tandem play at those positions.
November 2 - Steve Carlton won his 2nd Cy Young Award as his 23 wins helped The Phillies reached the postseason for the 2nd straight year, the first time the Phillies had consecutive postseason appearances.
November 22 – Andre Dawson of the Montreal Expos wins the National League Rookie of the Year Award by one vote over Steve Henderson of the New York Mets. Dawson hit .282 with 19 home runs and 65 RBI, while Henderson had .297, 12, 65.
April 3 – Hank Steinbacher, 64, outfielder for the Chicago White Sox from 1937 to 1939
April 12 – Philip K. Wrigley, 82, owner of the Chicago Cubs since 1932, and vice president of the National League from 1947 to 1966; also organized the All-American Girls Professional Baseball League in 1943
April 27 – Ernie Neitzke, 82, outfielder/pitcher for the 1921 Boston Red Sox
April 28 – Al Smith, 69, All-Star pitcher who won 99 games for Giants, Phillies and Indians
May 5 – Bill Marshall, 66, second baseman who played for the Boston Red Sox and Cincinnati Reds in the 1930s
June 10 – Turk Farrell, 43, All-Star pitcher who won 106 games, mainly with the Phillies and Astros
June 15 – Big Bill Lee, 67, All-Star pitcher who had two 20-win seasons for the Chicago Cubs
June 18 – Johnny Frederick, 75, slugger who hit .308 with 85 HR and 377 RBI in parts of six seasons for the 1930s Brooklyn Dodgers
July 16 – Milt Stock, 84, third baseman who batted .300 five times
August 16 – Al Javery, 59, two-time All-Star pitcher who played for the Boston Braves from 1940 to 1946
August 19 – Bob Klinger, 69, pitcher who compiled a 66-61 record for the Pirates and Red Sox from 1938 to 1947
August 19 – Chuck Wortman, 85, shortstop for the Chicago Cubs from 1916–18, who appeared in the 1918 World Series
September 2 – Chucho Ramos, 59, Venezuelan outfielder who played four games for the 1944 Cincinnati Reds
September 8 – Oral Hildebrand, 70, All-Star pitcher who won 83 games for the Indians, Browns and Yankees
September 14 – Beau Bell, 70, All-Star right fielder who led AL in hits and doubles in 1937; later coached at Texas A&M
September 24 – Sherm Lollar, 53, seven-time All-Star catcher for the Chicago White Sox who won first three Gold Gloves awarded
September 26 – Ernie Lombardi, 69, eight-time All-Star catcher, mainly with the Cincinnati Reds and New York Giants, who batted .306 lifetime and won 1938 MVP award; only catcher to win two batting titles, he caught Johnny Vander Meer's back-to-back no-hitters in 1938
September 30 – Del Pratt, 89, second baseman for four AL teams who led AL in RBI in 1916 with St. Louis Browns; batted .300 in his last five seasons
October 17 – Cal Hubbard, 76, Hall of Fame umpire in the American League from 1936 to 1951 who developed modern systems of umpire positioning
November 4 – Pinky Pittenger, 78, backup infielder/outfielder who played from 1921 through 1929 for the Boston Red Sox, Chicago Cubs and Cincinnati Reds
November 8 – Bucky Harris, 81, Hall of Fame manager of five teams who won 3rd most games (2,157) in history; managed Senators three times, winning 1924 World Series as rookie skipper, and also led Yankees to 1947 title; as second baseman, led AL in double plays five times
November 9 – Fred Haney, 79, manager who won World Series with Milwaukee Braves in 1957; was Angels' first general manager from 1960–68
November 17 – Roger Peckinpaugh, 86, shortstop for four AL teams who was named the 1925 MVP in his last full season; became manager and general manager of the Indians
November 24 – Mayo Smith, 62, manager of the Phillies, Reds and Tigers who led Detroit to the 1968 World Series title
November 28 – Bob Meusel, 81, outfielder, who batted over .300 seven times, including a career-high mark of .337 in 1927, hit for the cycle three times, and appeared in six World Series with the New York Yankees
December 1 – Dobie Moore, 82, star shortstop for the Negro Leagues' Kansas City Monarchs