January 28 – The New York Giants sign their first black players, outfielder Monte Irvin and pitcher Ford Smith, and assign them to a minor league affiliate at Jersey City. Irvin will eventually go on to have a Hall of Fame career for the Giants, but Smith never reaches the major leagues.
March 2 – A slumping Joe DiMaggio leaves spring training in Florida to have his ailing right heel examined at Johns Hopkins Hospital. DiMaggio is assured that surgery is unnecessary and returns to the Yankees. The as yet undiagnosed heel ailment will continue to plague DiMaggio throughout the season.
June 28 – After missing the first 65 games of the season due to a bone spur in his right heel, Joe DiMaggio awakes in early June to find the pain in his heel has disappeared. DiMaggio returns to the Yankee lineup with a home run and a single in a 5–4 win over the Boston Red Sox at Fenway Park. The crowd of 36,228 is the largest for a night game in Fenway history. With the win, the first-place Yankees move 4½ games ahead of the second-place Philadelphia Athletics and 6 games ahead of the third-place Red Sox.
June 29 – The Yankees come back from a seven-run deficit to defeat the Red Sox, 9–7. Joe DiMaggio belts two home runs in the win, a three-run shot in the fifth and a tie-breaking two-run blast in the eighth that provides the margin of victory.
June 30 – Joe DiMaggio belts his fourth home run in three games, a three-run shot off the left field light tower at Fenway Park. DiMaggio's home run powers the Yankees to a 6–3 victory and a three-game sweep of the Red Sox. The Red Sox drop to fifth-place, 8 games behind the front-running Yankees.
July 4 – At Yankee Stadium, the New York Yankees sweep a doubleheader against the Boston Red Sox, extending Boston's losing streak to eight games. The Yankees take the first game, 3–2, and the rain-shortened second, 6–4. The sweep leaves the Red Sox 12 games behind the first-place Yankees.
July 8 – Monte Irvin and Hank Thompson, called up three days earlier from Jersey City, become the first blacks to play for the New York Giants. Thompson starts at second base and Irvin pinch hits in the eighth. When Thompson steps in against Brooklyn DodgerDon Newcombe, it is the first time in major league history that a black batter and pitcher have squared off. The Dodgers win the game, 4–3.
A 16-inning affair between the Phillies and Braves ends at 1:01 a.m., becoming, to date, the latest-ending National League game in history. The Braves win the game, 4–3.
July 28 – Jackie Robinson raises his National League-leading batting average to .364 after a 12 for 25 streak. Robinson's average will drop, but he will win the batting title with a career-high .342 average.
August 7 – In the first game of a doubleheader against the Browns, Yankees catcher Yogi Berra suffers a fractured thumb when he is hit by a pitch after hitting a three-run home run in his previous at bat. The injury will keep Berra out of the Yankee lineup until September. The Yankees win the game, 20–2.
August 8 – Carl Furillo returns to the Dodgers' lineup after an injury and collects two hits and a run scored in Brooklyn's 2–1 win over the rival Giants. The win keeps the Dodgers tied with the Cardinals for first place. Furillo will hit .431 over the final eight weeks of the season and finish at .322, fourth best in the league.
August 9 – Dom DiMaggio's 34-game hitting streak comes to an end in the Boston Red Sox' 6–3 win over the Yankees at Yankee Stadium. Hitless in his first four at-bats, Dom hits a sinking line drive in the eighth that his brother Joe catches at the shoestrings. The resurgent Red Sox move within 5½ games of the Yankees with the win.
August 21 – The New York Giants receive a forfeit victory over the Philadelphia Phillies when fans at Shibe Park bombard the field with bottles after umpire George Barr rules that Phillie Richie Ashburn trapped a line drive. The forfeiture is the first in the majors since 1942. The Giants were leading 4–2 with one out in the ninth inning when the forfeit was declared.
The Boston Braves score two runs in the ninth inning to defeat the Brooklyn Dodgers, 7–6. One of the runs comes on Eddie Stanky's first home run of the season. The loss is Brooklyn's sixth in seven games and drops the Dodgers two games behind the Cardinals.
August 26 – With a doubleheader sweep of the White Sox, the Red Sox close to within 1½ games of the Yankees. The Red Sox win the first game, 11–4, behind Mel Parnell, who becomes the majors' first 20-game winner of the season, and Ted Williams, who slams his 31st and 32nd home runs of the season. The Red Sox take the second game, 10–7.
August 28 – In the first game of a doubleheader in Chicago, Tommy Henrich crashes into the wall while chasing a Chuck Kress fly ball and fractures two vertebrae. The injury will sideline Henrich for three weeks. In the second game, the newly acquired Johnny Mize dislocates his shoulder. With the exception of seven pinch-hit appearances, he will miss the rest of the regular season. The Yankees are also playing without Yogi Berra, who fractured his thumb earlier in the month. Despite the injuries, the Yankees sweep the doubleheader by scores of 8–7 and 7–5.
September 13 – Ralph Kiner ties a major league record held by six players with his 4th grand slam of the season. In the Pirates' 11–6 win over the Philadelphia Phillies, Kiner hits 2 home runs and drives in 6 runs. The 2 home runs come in his first 2 at-bats of the game. Kiner had homered in his final 2 at-bats in yesterday's game, making it 4 home runs in 4 consecutive at-bats over 2 games. It is the 2nd time in his career that Kiner has accomplished the feat.
September 14 – Ellis Kinder wins his 20th game of the season, shutting out the Detroit Tigers, 1–0, at Fenway Park. It is also Kinder's 10th consecutive win. Kinder joins teammate Mel Parnell as a 20-game winner. It is the last time this century that the Red Sox will feature a pair of 20-game winners.
The Cardinals and Dodgers split a doubleheader at Sportsman's Park, leaving the Cards in front by 1½ games. The Cards take the first game, 1–0, while the Dodgers answered back with a 5–0 win in the second.
September 22 – The Dodgers amass 19 hits and 13 walks in a 19–6 rout of the host Cardinals, bringing the Bums to within a 1/2 game of first-place. Carl Furillo has 7 RBIs for Brooklyn. In a losing effort, Stan Musial hits his 32nd home run of the season—his 21st against lefties, a major league record for a left-handed batter that will later be matched by Ken Griffey, Jr. in 1996 and 1998.
September 24 – At Fenway Park, the Red Sox defeat the Yankees, 2–0, to draw within a game of first-place New York. Ted Williams belts his 42nd home run and Ellis Kinder wins his 13th straight game, moving to 4–0 on the season against the Yankees.
The Yankees, in first-place all season despite 71 injuries that kept players out of games, fall into a first place tie with the Red Sox after losing to Boston, 4–1, at Fenway Park. Ted Williams hits his 43rd home run of the season, and Mel Parnell allows four hits in winning his 25th game of the season. Joe DiMaggio, still out of the lineup with pneumonia, listens to the game from his hospital bed.
September 26 – Before 67,634 at Yankee Stadium, the Red Sox come away with a 7–6 win and move into sole possession of first place when Johnny Pesky scores on a disputed squeeze play. The Sox rally from a 6–3 deficit by scoring four runs in the eighth. The winning run scores when Bobby Doerr drops a surprise squeeze bunt in front of Tommy Henrich, playing first base, and Pesky slides under the catcher's tag at home plate. Umpire Bill Grieve calls Pesky safe, and Casey Stengel is fined for a post-game confrontation with the ump. Now ahead by one game, the Sox depart for a three-game set in Washington before going back to New York for a final two-game showdown against the Yankees.
September 27 – Vic Raschi wins his 20th game of the season as the Yankees top the A's, 3–1. The Yankees remain one game back, however, by virtue of the Red Sox' 6–4 win over the Senators.
September 29 – The Cardinals fall to the Pirates and former Cardinal Murry Dickson, 7–2. It is Dickson's 5th win of the season against his former team. Meanwhile, the Dodgers sweep a doubleheader against the Braves, 9–2 and 8–0, moving them ahead of the Cardinals by a 1/2 game in the National League.
September 30 – The Red Sox move ahead of the Yankees by a game when they defeat the Senators, 11–9, and the Yankees are defeated by Dick Fowler and the A's, 4–1. Aided by 14 walks, the Sox win the game despite being outhit by the Senators, 18–5.
Ralph Kiner hits his 54th home run of the season and 16th in the month of September as the Pirates defeat the Reds, 3–2.
October 2 – A crowd of 70,000 packs Yankee Stadium to see the Yankees and Red Sox square off on the final day of the season with the American League pennant hanging in the balance. Phil Rizzuto scores the game's first run after tripling in the 1st. Vic Raschi nurses the 1–0 lead and duels Ellis Kinder into the 8th inning when the Yankees bust out and plate 4 runs off relievers Mel Parnell and Tex Hughson. The Red Sox rally for 3 in the 9th, but it's not enough, as the Yankees win the game, 5–3, and the pennant. Ted Williams is hitless in 2 official at-bats and goes 1 for 12 over the final four games of the season, enabling George Kell of the Tigers to edge Williams for the batting title, .3429 to .3427.
October 7 – With both the Series and game deadlocked at 1–1, the Yankees score 3 runs in the top of the 9th inning at Ebbets Field. The Dodgers answer with 2 runs in the bottom of the frame, but the Yankees hold on to win, 4–3, and take a 2–1 lead in the Series.