Both the Red Sox and Braves just learned that it takes 162 games to grab a playoff berth. Injuries, inexperience and the vagaries of the unbalanced schedule can turn contenders into pretenders in a heartbeat -- especially if another club gets hot down the stretch.

Baseball history is filled with stunning failures, from the 1951 Dodgers to the 1964 Phillies, but this year's reversals carved new niches in the annals of the game.

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On August 31, the Red Sox led the American League East by a game-and-a-half over the Yankees and nine games over the Rays. Less than a month later, on Sept. 26, the Yankees had clinched the division and the Rays had climbed into a tie with the Red Sox as the American League's wildcard leader.

Although the Sox led the majors in runs scored for the month, their pitching imploded. During one 20-game stretch, the team won only once in games in which they scored less than 12 runs.

Even the 1962 Mets, a hapless expansion team that finished with 120 losses, had a better September winning percentage than the 2011 Red Sox.

Atlanta's fate was similar even though its cause was different. The Braves owned an 8½ game lead over the Cardinals on Sept. 5 before suddenly slipping into a team-wide batting slump that persisted during a 3-6 stretch against the Mets, Nationals and last-place Marlins. Three-game road sweeps by the Cardinals and Phillies, plus losses in the first two games of a season-ending finale against the Phils at home, left the Braves and Cards tied for the wild-card going into the last day of the season.

On Wednesday night in the regular-season finales, the Red Sox and Braves both blew leads in the ninth inning. Boston closer Jonathan Papelbon gave up two runs to the Orioles, and the Sox lost 4-3. Atlanta led by one run in the ninth, but the Phillies tied it and won in the 13th. The Rays and Cardinals advanced by winning. Tampa Bay did it in dramatic fashion, wiping out a 7-0 deficit, tying it in the ninth and winning in the 12th.

It's hard to believe less than a month has passed since Boston owned the second-best record in the game, trailing only the Phillies. But losing 16 of its first 21 in September placed the team in a historic predicament.

The Red Sox and Braves will be remembered for epic collapses. But they aren't alone in baseball history. Here are some of the most memorable:

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    1942 Dodgers

    Brooklyn led the Cardinals by 9½ games on August 15 but couldn't hold on. Even victories in its last eight games weren't enough to stop St. Louis, which went 43-9 to win the NL flag by two games.

-- Former AP sportswriter Dan Schlossberg of Fair Lawn, N.J., is the author of 35 baseball books.

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