* The season was canceled due to a player's strike and the Mexican Pacific League's second place, Yaquis de Obregón, played as a replacement in the Caribbean Series.
February 11 – Dick Woodson becomes the first player to invoke the new free agency clause, seeking a $30,000 salary while the Minnesota Twins offer $23,000. The arbitrator sides with Woodson. On May 4, the Twins trade Woodson to the New York Yankees for Mike Pazik and cash.
February 13 – Cool Papa Bell is named for Hall of Fame honors by the Special Committee on the Negro Leagues.
February 23 – The California Angels send veteran Vada Pinson to Kansas City for a minor leaguer and cash consideration. Pinson will call it quits at the end of the 1975 season, having rung up 2,757 hits.
April 3 - The Cleveland Indians trade Pedro Guerrero to the Los Angeles Dodgers for pitcherBruce Ellingsen The 17-year-old infielder-outfielder will compile a.309 lifetime batting average and will be named to the all-star team five times during his 11 seasons with the team.
April 4 – Hank Aaron hits the 714th home run of his career, tying Babe Ruth's lifetime home run record.
April 6 – The New York Yankees defeat the Cleveland Indians 6-1 in their "home opener" at Shea Stadium. The Yankees will share this ballpark with the Mets for the 1974 and seasons, while Yankee Stadium is being re-furbished.
April 8 – Hank Aaron hits home run number 715, finally breaking Babe Ruth's lifetime home run record. Two fans run onto the field and congratulate him on the record breaking achievement as Hank moves past second base.
April 10 - The 1973 National League pennant is raised before the home opener in which The New York Mets defeat The St. Louis Cardinals, 3-2 in front of only 17,154 fans at Shea Stadium. Jerry Grote of the Mets homered in that game.
April 14 – Graig Nettles of the New York Yankees hits four home runs during a doubleheader split against his former team, the Cleveland Indians. The Yankees win 9–5, then lose 6–9. Nettles will go on to tie a major league record with 11 home runs in the month of April.
April 26 – The record breaking is not over for Hank Aaron. Today he hits his 15th career grand slam home run, passing Gil Hodges and Willie McCovey for the NL mark. The Braves go on to beat the Cubs, 9-3.
April 30 – At Fenway Park, Nolan Ryan of the Angels strikes out 19 Red Sox batters in a 4-2 victory. In a frightening moment, he hits second baseman Doug Griffin in the head with a fastball. Griffin will be sidelined for two months.
May 1 – Dock Ellis of the Pittsburgh Pirates hits three consecutive batters with pitches in the first inning, setting an ML record, and walks another in the frame before being lifted. Pittsburgh loses 5–3 to the Cincinnati Reds.
May 4 – Boston Red Sox shortstop Rick Burleson ties a major league record by committing three errors in his major league debut.
June 4 – The Cleveland Indians attempt an ill-advised ten cent beer promotion for a game against the Texas Rangers at Cleveland Municipal Stadium. Cleveland forfeits 9-0 after alcohol-fueled mayhem and violence spreads from the stands onto the field.
June 5 – Hank Aaron hits his 16th career grand slam homer as the Braves top the Phillies, 7-3, in Philadelphia.
June 11 – Mel Stottlemyre of the New York Yankees makes his 272nd consecutive start, with no relief appearances, to set an American League record.
June 14- California Angels pitcher Nolan Ryan pitches 13 innings, and strikes out 19 batters, including Red Sox first baseman Cecil Cooper, who alone struck out six straight times. The Angels defeated Boston 4-3 in 15 innings.
June 19 – George Scott, who walks to lead off the second inning, is the Brewers' only base runner as Steve Busby of the Kansas City Royals hurls a 2–0 no-hitter. Busby is the first major league pitcher to throw no-hitters in his first two seasons.
June 21 – The Braves fire manager Eddie Mathews, the only man to have played for the Braves in Boston, Milwaukee and Atlanta.
June 24 – Steve Busby of the Kansas City Royals retires the first nine batters he faces to set an American League record with 33 consecutive batsmen retired. The Royals lose, however, 3–1 to the Chicago White Sox.
July–September
July 11 – The San Diego Padres release outfielderMatty Alou. Alou's brother Felipe was released by the Milwaukee Brewers on April 29. Younger brother Jesús keeps the Alou name alive in the majors, playing for the Oakland Athletics.
July 14 – In a doubleheader with the Brewers, the Rangers' Billy Martin is the first American League manager to be removed by umpires from two games in one day.
July 17:
*Bob Gibson of the St. Louis Cardinals strikes out César Gerónimo of the Cincinnati Reds to become the second pitcher to strike out 3,000 batters in the majors. Gerónimo will become Nolan Ryan's 3,000th strikeout victim six years later.
*Milwaukee third baseman Don Money commits a first-inning error in a 10–5 loss to Minnesota, ending his perfect defensive season after 86 games and 257 chances. He will end the season with just five errors, breaking George Kell's record set in 1950. Money also holds the National League record with just 10 errors, set with the Phillies in 1972, and holds both the National League and American League records for most consecutive chances without an error in a season.
*Los Angeles Dodgers pitcher Tommy John, who started the season 13-3, has his season come to an abrupt end when he tears a ligament in his pitching elbow in the Dodgers 5–4 loss to the Montreal Expos.
July 19 – Dick Bosman of the Cleveland Indians no-hits the Oakland Athletics 4–0. Bosman has no one but himself to blame for not picking up a rare perfect game. His throwing error in the fourth inning puts the only A's runner on base. The two clubs combine to set an American League record with two runners left on base.
July 23 – The National League triumphs in the All-Star Game at Pittsburgh, winning 7–2 over the American League. Steve Garvey is named the MVP.
August 6 – Johnny Bench hits his 200th career home run helping the Cincinnati Reds beat the Los Angeles Dodgers 6-3.
August 12 – Nolan Ryan of the California Angels strikes out 19 in a 4-2 victory over the Boston Red Sox.
August 20 – Davey Lopes sets a Dodgers record when he totals 15 bases against the Cubs in an 18–8 drubbing at Wrigley Field. Lopes has three home runs, a double and a single in his team's 24-hit attack. The Dodgers totaled 48 bases in the game, a team record.
August 27 – Hal McRae of the Kansas City Royals ties a Major League record with six extra base hits.
September 3 – In an amazing performance, SF Giants' John Montefusco makes his major league debut, hits a home run in his first official time at bat off Charlie Hough, and pitches nine innings of relief to earn a 9–5 victory over the Dodgers.
September 4 – Pitcher Don Wilson has a no-hitter through eight innings, but is pulled from the game by Houston Astros manager Preston Gómez. Reliever Mike Cosgrove gives up a leadoff single to Tony Pérez, and the Astros lose to the Cincinnati Reds, 2–1. Gomez made the same mistake in San Diego on July 21, 1970. Clay Kirby had a no-hitter going for eight innings, but with two outs in the 8th and trailing 1–0, Gomez lifted him for pinch hitter Cito Gaston. Gaston failed to get a hit, and reliever Jack Baldschun gave up two runs in the 9th. The Padres lost 3–0.
September 7 – During a 3–1 win over the Chicago White Sox, Nolan Ryan of the California Angels has a fastball clocked at 100.8 miles per hour — the fastest pitch ever recorded.
September 8 – Pat Pieper ends 59-year career as public address announcer for the Chicago Cubs.
September 10 – CardinalLou Brock breaks Maury Wills' major league record by stealing his 104th and 105th bases of the season. It also gives him 740 career stolen bases, breaking Max Carey's National League record of 738.
September 11 – The St. Louis Cardinals win a marathon night game against the New York Mets at Shea Stadium, after seven hours four minutes, and 25 innings, the longest game to a decision in major league history. The Cardinals, trailing 3-1 with two out in the ninth, tie the score on Ken Reitz' two-run home run off Jerry Koosman, sending the game into extra innings. Two Mets errors lead to the Cardinals' winning run, starting with an errant pickoff throw that allows Bake McBride to scamper all the way around from first. St. Louis wins, 4–3. The Mets go to the plate 103 times, the only time the century mark has been reached in a major league game; the Cards are not far behind with 99 plate appearances. All told, a record 175 official at-bats are recorded, with a major-league record 45 runners stranded. Only a thousand fans are on hand when the game ends at 3:13 a.m.
September 12 – Tigers pitcher John Hiller picks up his 17th victory in relief, an American League record, as he beats the Brewers, 9–7.
September 24:
*Al Kaline of the Detroit Tigers doubles off Dave McNally for his 3,000th career hit, as the Tigers lose to the Orioles 5–4.
*Clarence Jones of the Kintetsu Buffaloes hits his 38th home run to become the first foreign player to win a home run title in Nippon Professional Baseball, topping the Pacific League. Sadaharu Oh will lead the Central League with 49 homers. Jones will lead the Pacific League again with 36 HR in 1976.
September 25 – Dodgers pitcher Tommy John undergoes surgery to repair the ulnar collateral ligament in his pitching elbow. The surgery, performed by Frank Jobe is now named after the pitcher.
September 28:
*In his last start of the year, Nolan Ryan of the California Angels pitches his third career no-hitter, victimizing the Minnesota Twins, 4–0. In the process, Ryan strikes out 15 batters for the sixth time this season. He also walks eight to run his season total to 202 bases on balls, joining Bob Feller in 1938 as the only pitcher to walk more than 200 in a season. Ryan will set a personal high issuing 204 walks in 1977.
*Don Wilson of the Houston Astros throws a 5–0, two-hit shutout against the Braves. It would be Wilson's last major league game, followed barely three months later by his accidental death.
October–December
October 3 – Frank Robinson becomes the first black manager in major league history, as the Cleveland Indians name him to replace Ken Aspromonte for the 1975 season.
October 17 – At the Oakland Coliseum, the Oakland Athletics win the World Series over the Los Angeles Dodgers in Game Five, clinching a third straight World Championship. Reliever Rollie Fingers is named the Series MVP.
October 23 – Wally Yonamine, an American of Japanese descent, becomes the only non-Japanese manager ever to win the Japan Series when his Chunichi Dragons beat the Lotte Orions.
November 2 – The Atlanta Braves trade Hank Aaron to the Milwaukee Brewers for outfielder Dave May and a minor league pitcher. Aaron will finish his major league career in Milwaukee, where he started it in 1954. Meanwhile, Aaron, the home run king of American baseball, and Sadaharu Oh, his Japanese counterpart, square off for a home run contest at Korakuen Stadium. Aaron wins 10–9.
*Commissioner Bowie Kuhn suspends New York Yankees owner George Steinbrenner for two years as a result of Steinbrenner's conviction for illegal campaign contributions to Richard Nixon and other politicians.
December 2 – The Boston Red Sox trade speedy outfielder Tommy Harper to the California Angels for infielder Bob Heise.
December 26 – The Little League is officially opened to girls as President Gerald Ford signs legislation amending the charter of the organization. Little League had sought changes in their charter after a series of lawsuits challenged its boys-only rule.
December 31 – After earning his freedom through arbitration over missed insurance payments by the Oakland Athletics, Jim "Catfish" Hunter is signed to a $3.75 million contract which is slightly more than triple the next highest salary in the game.
January 14 – Lloyd Brown, 73, pitcher who won 46 games for the 1930-32 Senators and also played with the Dodgers, Browns, Red Sox, Indians and Phillies.
January 20 – George Hockette, 72, pitcher for the Boston Red Sox in the mid-1930s.
February 13 – Scrip Lee, 75, Negro league baseball pitcher from 1921 to 1934.
February 20 – Bob Christian, 28, outfielder who played from 1968-70 for the Detroit Tigers and Chicago White Sox.
March 1 – Larry Doyle, 87, second baseman, primarily for the New York Giants whom he captained, who batted.300 five times and won the NL's 1912 MVP award; led NL in hits twice and stole home 17 times.
March 14 – Alex Pompez, 83, owner of the Negro Leagues' Cuban Stars and New York Cubans between 1916 and 1950, who later became a scouting director for the New York Giants.
April 5 – Fred Snodgrass, 86, center fielder for the New York Giants who made a critical drop of an easy fly ball in the tenth inning of the deciding game in the 1912 World Series.
April 6 – Roy Wood, 81, outfielder/first baseman who played from 1913-15 for the Pittsburgh Pirates and Cleveland Naps/Indians.
April 22 – Steve Swetonic, 70, pitcher for the Pittsburgh Pirates in the early 1930s, who tied for the National League lead in shutouts in the 1932 season.
April 23 – Cy Williams, 86, center fielder for the Cubs and Phillies who became the first National League player to hit 200 home runs, leading the league four times.
May 5 – Vito Tamulis, 62, left-handed pitcher who posted a 40-28 record with a 3.97 ERA in six seasons for the Yankees, Browns, Dodgers and Phillies.
May 18 – Dan Topping, 61, co-owner and president of the Yankees from 1945 to 1964, during which time the team won ten World Series and fifteen AL pennants.
June 30 – Mule Haas, 70, center fielder for the Athletics and White Sox, who hit two home runs in the 1929 World Series.
July 4 – Del Webb, 75, co-owner and chairman of the Yankees from 1945 to 1964; co-owner Dan Topping had died just weeks earlier.
July 17 – Dizzy Dean, 64, Hall of Fame pitcher who won MVP award in 1934 with 30-7 campaign, the last 30-win season by an NL pitcher; was MVP runnerup the next two years, but an injury in 1937 All-Star game led to end of career; became a broadcaster known for folksy mangling of the English language.
August 8 – Howie Pollet, 53, All-Star pitcher who twice won 20 games for the St. Louis Cardinals.
September 19 – Zack Taylor, 76, NL catcher for fifteen seasons, later a coach, manager and scout for 35 years.
September 25 – Cliff Brady, 77, a second baseman for the Boston Red Sox and minor league manager, who also was a member of the Scullin Steel soccer team which won the National Challenge Cup in 1922.
September 26 – Lefty Stewart, 74, pitcher who won 20 games for the 1930 St. Louis Browns.
October 13 – Sam Rice, 84, Hall of Fame right fielder for the Washington Senators who batted.322 lifetime and led AL in steals and triples once each, remembered for disputed catch in 1925 World Series; finished career with 2,987 hits, at a time when little attention was paid to career totals.
October 22 – Pat Pieper, 88, the Chicago Cubs field announcer from 1916 to 1974, a span of 59 years.
October 31 – Buddy Myer, 70, All-Star second baseman for the Washington Senators who batted.303 lifetime and won 1935 batting title.
December 18 – Harry Hooper, 87, Hall of Fame right fielder for the Boston Red Sox and Chicago White Sox, who was an outstanding defensive player and solid leadoff hitter, helping the Red Sox to four champion titles, while retiring with the fifth-most walks in history.