Trying to avoid being swept for the first time in more than six weeks, the NL East-leading Nationals go for a rare win over Cole Hamels on Thursday night.Washington (61-42) entered this series having won eight of nine -- averaging 6.9 runs in those victories -- but it has been unable to get much going offensively against the Phillies (47-57). In Tuesday's opener, Cliff Lee and three relievers combined for a five-hitter in an 8-0 win, then Vance Worley and the bullpen limited the Nationals to seven hits in a 3-2 victory Wednesday.Washington, which still owns a 2 1/2-game division lead over Atlanta, is 4-4 against a Philadelphia team 14 1/2 games back. It is 21-12 against the rest of the division.The Nationals have their work cut out for them to avoid being swept for the first time since dropping three to the New York Yankees from June 15-17.Hamels (11-5, 3.31 ERA) has gone eight innings in winning each of his two starts against Washington this season, permitting one total run while striking out 16. That kind of mastery over the Nationals is nothing new, as he's 9-2 with a 2.15 ERA in his last 14 starts against them and 5-0 with a 1.80 ERA in his last nine outings in the nation's capital.The left-hander has allowed nine hits against Washington this year, and Bryce Harper has three of them in six at-bats.Harper had two singles Wednesday after going 2 for 24 with 10 strikeouts in his final six July games, while Adam LaRoche drove him in with a single. LaRoche, who is 4 for 19 with three homers lifetime against Hamels, is batting .394 with three home runs and seven RBIs during a season-high nine-game hitting streak.Philadelphia scored all its runs Wednesday on solo homers -- two from Jimmy Rollins and one by Nate Schierholtz.Schierholtz started in right field and went 2 for 5 a day after being acquired from San Francisco in the deal that sent Hunter Pence to the Giants."We've got some life to us," Phillies manager Charlie Manuel said. "We're having fun. We've got some guys that are trying to really show something, and hopefully we can get better."Rollins also homered Tuesday and is 6 for 15 with three doubles against scheduled Washington starter Ross Detwiler (5-4, 3.24), who will make his first start against the Phillies since yielding three hits in 7 1/3 innings of a 3-0 win Sept. 20.Detwiler, though, lasted just 4 2/3 innings Friday at Milwaukee, allowing four runs and seven hits in a 6-0 loss. It was his first defeat since May 19, a span of seven starts."I don't think you can feel too good about that," said the southpaw, who had a 2.35 ERA in his previous five outings.Hamels is also coming off a shaky performance. He struggled mightily with his control in Atlanta on Friday, setting a career high with six walks in a season-low five innings. He allowed five runs -- three earned -- and four hits while striking out seven in a 6-1 loss.The start came two days after he signed a $144 million, six-year contract extension, and he thought some of the emotions that came with the massive deal factored in his subpar showing."It was a long week," Hamels said. "I don't think I'll have to experience that again."