The following are the events that happened world-wide throughout the sport of baseball.
- 1899 - John McGraw, at age 26, made his managerial debut with the Baltimore Orioles of the National League. McGraw led them to a 5–3 victory over the New York Giants, a team he later managed for more than 30 years.
- 1916 - Grover Alexander of the Philadelphia Athletics pitched his first of 16 shutouts of the season against the Boston Braves.
- 1923 - The debut of Yankee Stadium is a huge success with an announced attendance of 74,217. Bob Shawkey of the Yankees, aided by a three-run home run by Babe Ruth, beats Howard Ehmke and the Red Sox 4–1.
- 1925 - Brooklyn Dodgers owner Charles Ebbets dies of a heart attack at his Waldorf-Astoria apartment at the age of 64. Later in the day, his team opens the home season losing to the New York Giants at Ebbets Field, 7–0.
- 1929 - At Yankee Stadium, Babe Ruth hits a home run in his first at-bat since his marriage yesterday. As he rounds second base tips his hat to his new bride, Claire Merritt Hodgson.
- 1939 - Announcer Red Barber calls the action in the Brooklyn Dodgers 7–3 loss to the New York Giants, marking the first time a regular season Brooklyn game is broadcast on the radio.
- 1942 - Due to the fear of a Japanese attack, west coast military leaders ask the Pacific Coast League to limit crowds to 3,000 fans.
- 1946 - Jackie Robinson makes his minor league debut for the Montreal Royals, the International League affiliate club of the Brooklyn Dodgers. In becoming the first black to play Organized Baseball in the 20th century, Robinson bangs out a home run and three singles on his way to winning the league batting championship.
- The first opening night game was held in St. Louis. The Cardinals, behind a complete game by Gerry Staley and home runs from Red Schoendienst and Stan Musial, beat the Pirates, 4–2, at Sportsman's Park.
- At the Polo Grounds, Sam Jethroe becomes the first black to play for the Boston Braves. A former Cleveland Buckeyes star, he goes 2-for-4, including a home run to lead the Braves to an 11–4 beating of the New York Giants. Warren Spahn is the winner. Jethroe will go on to become National League Rookie of the Year after lead the majors in stolen bases.
- U.S. President Harry Truman throws out two balls at the Washington Senators opener—one left-handed and the other right-handed—then watches the Senators beat the Philadelphia Athletics 8–7. When rain starts falling in the sixth inning, he puts on a raincoat and remains to the end.
- At Fenway Park, Commissioner Happy Chandler gives Ted Williams his American League MVP Award, and then Governor Paul Dever tosses out the first ball. To the delight of 31,822 fans, Boston rips New York Yankees starter Allie Reynolds with a five-run fourth inning to drive him from the game and take a 9–0 margin. But the Yankees score four runs in the sixth off Mel Parnell and then, down 10–4, New York unloads for nine runs in the eighth. Billy Martin becomes the first player in major league history to get two base hits in one inning in his first ML game. He doubles against Parnell on his first at bat in the eighth inning, and singles off Al Papai. Walt Masterson gives up Tommy Henrich's second triple of the game before giving way to four more Boston pitchers. Boo Ferriss, pitching in his last game, allows the last two runs in the ninth inning as the Yankees chalk up a 15–10 victory, the biggest blown lead the Red Sox have ever had at Fenway (on June 4, 1989, they'll blow a 10-run lad at home). Joe DiMaggio, Yogi Berra, Vern Stephens, and Bobby Doerr each have three hits. Don Johnson is the winning pitcher, his last one for New York, with Joe Page pitching a perfect eighth and ninth innings in relief.
- 1951 - Mickey Mantle makes his major league debut for the New York Yankees. Mantle picks up one hit in two official at-bats, as the Yankees defeat the rival Boston Red Sox, 6–1, behind the pitching of Eddie Lopat.
- 1956 - Ed Rommel becomes the first major league umpire to wear glasses during a game as he arbitrates a contest between the Yankees and Senators.
- 1958 - The Los Angeles Dodgers play their first game at the Los Angeles Coliseum in front of a crowd of 78,672. Carl Erskine gets the win besting Al Worthington and the San Francisco Giants, 6–5.
- 1964 - Sandy Koufax of the Los Angeles Dodgers strikes out the side on nine pitches, becoming the first pitcher in major league history to achieve the feat twice. In spite of this third-inning dominance against the Cincinnati Reds, Koufax loses the game, 3–0.
- 1966 - At Astrodome, the Houston Astros and Los Angeles Dodgers play the first regular season game on AstroTurf as the Dodgers defeat the Astros, 6–3. Don Sutton earns his first major league victory while fellow Robin Roberts takes the loss.
- In International League action at McCoy Stadium, the Pawtucket Red Sox and Rochester Red Wings start the longest game in professional baseball history. The game is suspended at 4:07 AM the next day, after playing to a 2-2 tie through 32 innings. The game will be resumed in June with the Red Sox scoring the winning run in the 33rd inning. The 33-inning contest will last a total of eight hours and 25 minutes.
- Tom Seaver of the Cincinnati Reds notches the 3,000th strikeout of his Hall of Fame career. Seaver strikes out Keith Hernandez of the St. Louis Cardinals, joining Bob Gibson, Walter Johnson, Gaylord Perry, and Nolan Ryan as members of the exclusive pitching club.
- 1982 - At Astrodome, the Atlanta Braves defeated the Houston Astros, 6–5, to set a National League record as they won their 11th straight game to start the season. Al Habrosky was the winner and Rick Camp earned the save. Dave Smith was the loser.
- 1987 - Mike Schmidt of the Philadelphia Phillies hit his 500th home run off Don Robinson with two outs in the ninth inning to rally the Phillies to an 8–6 victory over the Pittsburgh Pirates at Three Rivers Stadium.
- 1991 - A sellout crowd of 42,191 watch the Chicago White Sox play their first game at new Comiskey Park and sees the home team get crushed by the Detroit Tigers, 16–0. Jack McDowell gives up the park's first home run to Cecil Fielder.
- 1997 - Roger Pavlik of the Texas Rangers became the first pitcher in American League history to walk the first four batters of the game in a 6–5 loss to the Toronto Blue Jays.
- 2000 - Adam Kennedy of the Anaheim Angels tied a club record with eight RBI and came within a double of the cycle as Anaheim defeated Toronto at he SkyDome, 16–10.
- The New York Yankees scored 13 runs in the second inning of a 19–8 victory over Tampa Bay. The last time New York scored 13 runs in an inning was on June 21, 1945, in the fifth inning of a 14–4 victory against Boston.
- Tim Hudson outpitched Roger Clemens, and rookie Ryan Langerhans pinch-hit an inside-the-park home run in the 12th inning off Dan Wheeler, to lead the Atlanta Braves to a 1–0 victory over the Houston Astros at Minute Maid Park.
- Hanley Ramírez of the Florida Marlins hit his first major league career home run, and later added a second blast, collecting four RBI, in Florida's 12–6 victory over Cincinnati.
- Luis Gonzalez of the Arizona Diamondbacks doubled to become the 21st major leaguer with 300 home runs and 500 doubles, as the Diamondbacks defeated San Francisco 7–4. Gonzalez joins a list led by Hank Aaron, who hit 755 homers and 624 doubles. The only other active player in the group is Barry Bonds, who hit his 567th double in the game.
- For the first time since its first month of play, the Houston Astros has a .500 franchise record. With a 13–12 victory against the Milwaukee Brewers, the Astros became the 13th team in the majors with a record of .500 or better. The victory put the franchise at .500 for the first time since the Colt .45s, as the team was known, were 6-6 before a 2–1 loss to the Milwaukee Braves on April 27, 1962. The franchise record is 3,507-3,507. Carlos Lee went 4-for-5 with a pair of two-run home runs for Milwaukee.
- Víctor Martínez of the Cleveland Indians extended his hitting streak to 13 games, going 3-for-6 in Cleveland's 15-1 rout of Baltimore.
- The Kansas City Royals has lost nine games in a row following a 4-1 defeat to the Chicago White Sox, its longest skid since its team-record 19-game losing streak late last year. The Royals are a major league-worst 2-11.
- Albert Pujols hit his major league leading 10th home run in St. Louis' 12–4 loss to Pittsburgh.
- 1880 - Sam Crawford, Hall of Fame outfielder (d. 1968)
- 1888 - Duffy Lewis, outfielder (d. 1979)
- 1983 - Miguel Cabrera, All-Star OF/IF
- 1986 - Billy Butler, 1B/DH