The largest division deficits overcome at any point in September to make the postseason:
1978 New York Yankees: 6½ games back on Sept. 2.
1995 Seattle Mariners: 6 games back on Sept. 8.
1973 New York Mets: 5½ games back on Sept. 6.
1969 New York Mets: 5 games back on Sept. 4.
1974 Baltimore Orioles: 5 games back on Sept. 2.
1978 New York Yankees
In what was probably the most memorable September deficit overcome, the Yankees trailed the
Red Sox by 6½ games on Sept. 2. After winning five of their first seven games in September,
the Yankees traveled to division-leading Boston with their deficit cut to four games.
The Yankees swept the four-game series, known as "Boston Massacre," outscoring the Red Sox 42-9 to move into a first-place tie. After taking two of three from the Red Sox the following weekend at Yankee Stadium, the Yankees had a 2½-game lead in the division.
The Sox went 11-2 over the last 13 games to pull even with the Yankees on the last day of the season. After 162 games, the two teams were tied with a 99-63 record.
They met in a one-game playoff at Fenway Park to decide the division winner. In what is now known as "The Bucky Dent Game," the beleaguered Yankees shortstop gave the Yankees a 3-2 lead with a three-run home run in the seventh inning off former Yankee Mike Torrez. Trailing 5-4 going into the ninth, the Red Sox put the tying run on third before Goose Gossage got Carl Yastrzemski to pop out, giving the Yankees their third straight AL East division championship.
1995 Seattle Mariners
"Refuse to lose" was the rally cry as Seattle fans watched the Mariners rally from six games back on Sept. 8 to win the AL West. The Mariners then won 16 of their last
19 games to take a two-game lead over the Angels, who went 8-11 over the same stretch. Needing to win just one of their final two games at Texas, the Mariners lost both games, while the Angels won their final two games in Anaheim against the A's to force a one-game playoff. Leading 1-0 heading into the bottom of the seventh inning, the Mariners scored eight runs over the last two innings to win their first division title. Randy Johnson struck out 12 in a complete game.
1973 New York Mets
On Sept. 6, the Mets stood in fourth place -- 5½ games behind the first place St. Louis Cardinals. The Mets went 16-6 the rest of the way, including a 10-3 record against the three teams in front of them. Perhaps the fate of the NL East was decided on Sept. 20 against the Pirates at Shea Stadium. In a tie game in the top of the 13th inning, Pittsburgh's Jerry Augustine hit a long fly ball that appeared to be a two-run homer. The ball amazingly hit off the top of the wall, as left fielder Cleon Jones caught the carom and threw home to nail Richie Zisk at the plate. The Mets won the game in the bottom of the inning and moved into first place for good the next day.
1974 Baltimore Orioles
The Orioles rallied from a five-game deficit on Sept. 2 to win the AL East. Trailing the Yankees by 1½ games on Sept. 13, the Orioles went 16-2 the rest of way to win the division by two games. Their two defeats: a 1-0 shutout loss by Gaylord Perry, and a 6-5 extra-inning loss in which the Orioles blew a four-run ninth-inning lead to the Red Sox at Fenway. Perhaps Baltimore's most memorable win in the span was a 17-inning 1-0 win over the Brewers which saw starters Jim Palmer and Jim Colborn throw 12 and 13 shutout innings, respectively. Bobby Grich scored the game-winning run on a fielder's choice by Bob Oliver.
1969 New York Mets
The "Miracle Mets" were five games behind the NL East-leading Chicago Cubs on Sept. 4. Five days later, the Mets completed a two-game sweep of the Cubs at Shea Stadium. The highlight of the game was a black cat running in front of the Cubs' dugout. After defeating the Expos 3-2 in the first game of a doubleheader on Sept. 10, the Mets vaulted into first place for the first time in their history. On Sept. 24, Gary Gentry threw a four-hit shutout against the Cardinals as the Mets wrapped up their first division title in team history, completing a stretch in which they went 19-5 and the Cubs went 6-14.
Bonus race ... 1972 AL East
On Sept. 1, the Baltimore Orioles led the division by 1½ games ahead of the Tigers and Yankees and two games ahead of the Red Sox. On Sept. 4, a half game separated the four teams. Each team spent time in first place, but no team had more than a 1½-game lead.
From Sept. 1 until Sept. 28, no more than four games separated the four teams. After a 3-2 extra-inning loss to to the Yankees (Roy White homered to win the game in the 12th inning), the Tigers fell 1½ games behind the first-place Red Sox. The Tigers then swept a three-game series vs. Milwaukee, setting up a season ending three-game set at Tiger Stadium to determine the AL East champion.
In the first game of the series, Al Kaline's first-inning home run off Jack Curtis sparked the Tigers and a Luis Aparicio baserunning blunder cost the Red Sox an early run. Mickey Lolich pitched a masterful six-hit complete game, striking out 15 Red Sox batters. The Tigers' 4-1 win gave them a half-game lead over the Sox with two games remaining. In the second game of the series, the Tigers received another strong pitching performance, this time from Woody Fryman, who only allowed one unearned run over 7 2/3 innings. Kaline again starred for the Tigers collecting two hits and scoring the go-ahead run in the seventh inning on a Carl Yastrzemski error. The Tigers wrapped up their first AL East division title.
The Red Sox would go on the win the series finale, 4-1 on a Marty Pattin four-hitter, leaving them a half game out. It's interesting to note that a players' strike wiped out the first week of the season. Major League Baseball decided not to reschedule any games, but to just go with the remaining schedule ignoring the fact that teams played a different number of games. This played a major factor in the AL East, as the Red Sox played one less game than the Tigers and finished a half-game back. (The Tigers played 156 games, Red Sox 155).
Mark Kelly is a ESPN researcher. He can be reached at firstname.lastname@example.org