If the Washington Nationals are going to make the much-anticipated, still-absent run that validates their expectations, they first need to find a launching point. This week seemed to provide the ideal moment. Bryce Harper returned Monday, the Nationals scored double-digit runs in consecutive games and the Milwaukee Brewers would remain at Nationals Park for another three days. The Nationals, at last, would take off. The perfect conditions have yielded the same disappointing results, all spinning wheels and no progress. The Nationals fell back to .500 Wednesday night with their 4-1 loss to the Brewers, avoiding consecutive shutouts only because Anthony Rendon drilled a solo home run into the visitors’ bullpen in the seventh inning. Kyle Lohse carved through the Nationals for eight innings, and the 23 runs they scored Sunday and Monday felt more like a blip than a spark. “I don’t have any answers,” Manager Davey Johnson said. “Just kind of nothing. Can’t get nothing going. It’s putting me in the loony bin.” Lohse and Ross Detwiler squared off in a pitching rematch of Game 4 of last year’s National League Division Series, and this time Lohse won. He gave up four hits and one walk and struck out seven. Detwiler, meanwhile, allowed four runs in six innings, two of them scoring after Harper dropped a line drive. Once Lohse exited, the Nationals threatened. Ryan Zimmerman singled and Ian Desmond drew a two-out walk in the ninth off Francisco Rodriguez to bring Rendon to the plate as the tying run. The crowd rose as Rendon drilled a deep flyball to center field, but he knew right away he had not hit it far enough. The drive died on the warning track, and roars turned to groans.