Momentum escapes Dodgers yet again in 4-1 loss to Nationals September called, and the Dodgers answered with mediocrity. With constant, predictable mediocrity. When they look back on their 2012 season, they can stare at a stretch drive that offered opportunity and how they completely wasted it. The Dodgers have struggled the entire second half to create any real positive momentum, and however thrilling Matt Kemp's game-winning homer proved Wednesday, there was no carryover to be found by Thursday. Just like most every time. Instead, the Dodgers played another uninspired offensive game, falling 4-1 to the Nationals to further fall off the postseason map. All while the Nationals were joining the Reds in clinching a National League playoff berth today. The loss left the Dodgers three games back of the Cardinals for the second NL wild-card spot. Worse, they were passed in the standings by the hot Brewers, who are 2 1/2 games back. Meanwhile, the Phillies trail the Dodgers by only one game. The Dodgers have 12 games left to their regular season. If it feels like it's all slipping away for the Dodgers, it should be familiar. The Dodgers are now 7-10 in September. Since July 23, they are 24-29. Despite the new weapons, they remain an underperforming offensive team. On Thursday they managed only four hits. They could do almost nothing with Washington starter Ross Detwiler, who retired the first nine Dodgers before Mark Ellis led off the fourth inning with a solo home run. Detwiler (10-7) went six innings, holding the Dodgers to three hits, with one walk and five strikeouts. Three Nationals relievers held the Dodgers scoreless over the final three innings. Chris Capuano again pitched OK, but not well enough. Which pretty much has been his story for awhile now. In his first 15 starts, Capuano was 9-2 with a 2.60 earned-run average. In his last 16 starts, he is 2-9 with a 4.65 ERA. Thursday he gave up four runs (three earned) in five innings, though he wasn't exactly supported by the Dodgers" finest defense. The Nationals scored twice in the third and fourth innings. Ryan Zimmerman doubled in the first run, and after advancing to third on a groundout, scored when a Capuano pitch went between catcher A.J. Ellis" legs. It was ruled a wild pitch. Washington scored two more in the fourth after Ian Desmond doubled in a run and took third when shortstop Hanley Ramirez's relay went wide of the plate for an error. He then scored on a Kurt Suzuki sacrifice fly. All that was left was for the Nationals to celebrate advancing to the playoffs. That thing the Dodgers seem unable to grasp. More on Matt Kemp's big Wednesday night Frank McCourt: The gift that keeps on giving