February 19 – Commissioner Bowie Kuhn announces the suspension of Detroit Tigers pitcher Denny McLain, effective April 1, for McLain's alleged involvement in a bookmaking operation. The suspension is indefinite, but will later be set at three months.
April 1 – The Milwaukee Brewers organization, headed by Bud Selig, purchases the Seattle Pilots franchise for $10,800,000. Although negotiations were conducted over a period of months, it was not until March 13 when a federal bankruptcy referee declared the Pilots bankrupt. Brewers tickets go on sale the next day. Team equipment is shipped to Milwaukee County Stadium, where the Pilots insignia is ripped off of the uniforms, since there is no time for new uniforms to be made.
Major league baseball returns to Wisconsin after a 4-year absence as the Brewers play their first game in Milwaukee, losing to the California Angels 12–0 before a crowd of 37,237.
Pitcher Dave McNally strikes out 13 in nine innings as the Baltimore Orioles rip the Indians, 8-2, in Opening Day at Cleveland Stadium. The attack is led by Paul Blair, who drives in a pair of runs and scores three times. McNally holds the Indians to two runs on four hits and three walks to get the win. Rookie Roy Foster belts a two-run home run for the only offense for Cleveland.
April 22 – The New York Mets' Tom Seaver strikes out 19 San Diego Padres, including the last 10 in succession, in winning 2-1 for the Mets. Mike Corkins takes the loss. In this century, no one had ever struck out 10 in a row, a major league record. Counting the 10 whiffs, the Pads have struck out 29 times in two games, a National League record that will be topped in 1998 when the Houston Astros miss 31 times in two days. Jerry Grote adds one foul fly catch to his 19 putouts via K's.
May 10 – Hoyt Wilhelm makes his 1,000th pitching appearance; the first pitcher in history to do so.
May 17 – In the second game of a double header, Hank Aaron of the Atlanta Braves gets his 3000th career hit, and is the founding member of the 3000-500 Club.
June 5 – Bert Blyleven makes his major league debut, and gives up a lead-off home run to Washington's Lee Maye. Blyleven holds on for a 2-1 win, the first win of the 287 that will propel his career into the Hall of Fame.
July 16 – Pittsburgh's Three Rivers Stadium was opened to the public, but the Cincinnati Reds spoiled the party as they beat the Pittsburgh Pirates 4-3 before a crowd of 48,846. The first hit at Three Rivers Stadium was a single by Pittsburgh's Richie Hebner. The first home run at Three Rivers Stadium was hit by Cincinnati's Tony Pérez.
July 26 – Johnny Bench of the Cincinnati Reds hit three straight homers off Steve Carlton of the St. Louis Cardinals. On the same day, Orlando Cepeda of the Atlanta Braves connected for three consecutive homers in an 8-3 victory over the Chicago Cubs.
October 1 – Vic Davalillo of the St. Louis Cardinals against the Pittsburgh Pirates breaks the National League single-season pinch hitting record and ties the Major League record with his 24th pinch hit of the year. Also, the Phillies defeated the Montreal Expos 2-1 in 10 innings in the final game at Shibe Park (Connie Mack Stadium). The occasion was marred by people literally dismantling the stadium while the game was still in progress. A special post-game ceremony — including a helicopter delivery to Veterans Stadium of home plate — was cancelled.
November 25 – New York Yankees catcher Thurman Munson receives 23 of 24 first-place votes and is named American League Rookie of the Year. Munson batted .302 with six home runs and 53 RBI during the regular season. Cleveland Indians outfielder Roy Foster (.268, 23, 60) is also named on a first place ballot.
November 27 – Pitcher Carl Morton, who posted an 18-11 record with 154 strikeouts and a 3.60 ERA for the last-place Montréal Expos, receives the National League Rookie of the Year Award. Morton beats out Cincinnati Reds outfielder Bernie Carbo, who hit .310 with 21 home runs and 63 RBI.
February 5 – Rudy York, 56, Hall of Fame first baseman and seven-time All-Star who had six 100-RBI seasons for the Detroit Tigers and Boston Red Sox, while hitting a record 18 homers in one month as a rookie, and two grand slams in a 1946 game.
April 8 – Lee Handley, 57, an infielder for the Pittsburgh Pirates during eight seasons, who also played with the Cincinnati Reds and the Philadelphia Phillies.
April 11 – Joe Heving, 69, a pitcher for the Giants, White Sox, Indians, Red Sox and Braves between 1930 and 1945, who led American League pitchers with 63 appearances in 1944, despite being the only grandfather playing in the majors.
April 11 – Sailor Stroud, 84, pitcher who posted a 5-7 record with a 3.25 ERA and three shutouts for the Detroit Tigers (1915) and New York Giants (1916).
June 1 – George Watkins, 69, outfielder for the St. Louis Cardinals, New York Giants, Philadelphia Phillies and Brooklyn Dodgers in the early 1930s, who owns the major league season-record for a rookie with a .373 batting average (1930).
June 3 – Jakie May, 74, relief pitcher for the St. Louis Cardinals, Cincinnati Reds and Chicago Cubs in 14 seasons spanning 1917–1932, who posted a 72-95 record with a 3.88 ERA and 19 saves in 1562 innings of work.
June 14 – Webbo Clarke, 42, Panamanian pitcher who played for the 1955 Washington Senators.
June 23 – Ross Reynolds, 82, pitcher who posted a 5-4 record and a 2.62 ERA for the 1914–1915 Detroit Tigers.
July 1 – Herb Hall, 77, pitcher for the 1918 Detroit Tigers.
July 7 – Harry Wolter, 85, outfielder and pitcher who played for the Cincinnati Reds, Pittsburgh Pirates, St. Louis Cardinals, Boston Red Sox, New York Highlanders/Yankees and Chicago Cubs.
July 8 – Jimmy Grant, 51, third baseman who played from 1942 through 1944 for the Chicago White Sox and Cleveland Indians.
July 15 – Emilio Palmero, 75, Cuban pitcher who spent over 17 years in baseball, including stints with the New York Giants, St. Louis Browns, Washington Senators and Boston Braves during five seasons spanning 1915–1928.
July 16 – Peahead Walker, 71, who had a distinguished minor league career as player and manager, and later became a prolific football coach with several collegiate squads as well as the CFL's Montreal Alouettes.
July 24 – Harvey Green, 55, pitcher who played for the Brooklyn Dodgers in the 1935 season.
July 25 – Herb Hunter, 74, utility IF/OF for the New York Giants, Chicago Cubs, Boston Red Sox and St. Louis Cardinals between 1916 and 1921.
July 27 – Whitey Platt, 29, backup outfielder for the Chicago Cubs, Chicago White Sox and St. Louis Browns in five seasons between 1942 and 1949, who was a member of the 1938 United States national team in the inaugural Amateur World Series played in England, and also served with the US Navy in the Pacific Theatre of World War II.
July 29 – Charley Moore, 85, infielder for the 1912 Chicago Cubs.
November 24 – Ivy Andrews, 63, pitcher for three American League teams from 1931–1938 and a member of the New York Yankees 1932 World Champions, who later became the first pitching coach for the Double-A Birmingham Barons.
December 10 – Johnny Mostil, 74, center fielder for the Chicago White Sox whose promising career was derailed by a 1927 suicide attempt.
December 12 – Doug Taitt, 68, right fielder for the Boston Red Sox, Chicago White Sox and Philadelphia Phillies from 1938 to 1932, who later became a successfully hitter and manager in the Minor Leagues.