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The Washington Nationals defeated the Los Angeles Dodgers, 4-1, on Thursday night and secured the first postseason berth for a Washington team since the Senators reached the World Series in 1933, adding another milestone to the Nationals’ magical season.

Ross Detwiler stifled the Dodgers for six innings, limiting them to one run on three hits. Christian Garcia and Ryan Mattheus combined to pitch the next two scoreless innings. Drew Storen notched the save to secure the victory.

Ryan Zimmerman smacked an RBI double in the third inning to score Bryce Harper, and Zimmerman scored on a wild pitch as Michael Morse was batting to give the Nationals a 2-0 lead in the inning. They added two more runs later on an RBI double by Danny Espinosa in the fourth inning and a sacrifice fly by Kurt Suzuki that scored Espinosa.

The Nationals, who also have the best record in baseball, improved the National League East lead over the idle Atlanta Braves to 5 ½ games with 12 games left. The magic number to claim the division title was trimmed to eight, a combination of Nationals wins and Braves losses.