Washington, DC (Sports Network) - Brandon Backe threw seven-plus shutout innings and had two hits, while Carlos Lee went 2-for-4 with three runs batted in, as Houston blanked Washington, 5-0, in the rubber match of a three-game series.

Backe (6-9) scattered five hits, walked four and struck out five, and picked up his first win since June 22. It was also just his second win in his past nine starts.

"He was outstanding," Houston manager Cecil Cooper said of Backe. "He was 2- for-3. He scored a couple of runs. He pitched like we knew he could pitch. He had all his pitches working. He had command of his fastball. I was prepared to let him go as long as he kept getting outs. I wanted him to have a chance to get his shutout."

Ty Wigginton went 2-for-3 with a solo homer for the Astros, who have won two in a row and go into the All-Star break with a 44-51 record, in last place in the National League Central.

Odalis Perez (2-7) threw six innings and gave up three runs on nine hits, while striking out six. He lost his second straight start and third straight decision.

Wil Nieves' double was the only extra-base hit for the Nationals, who have lost nine of 11 and go into the break with a 36-60 mark -- 16 games behind NL East-leading Philadelphia, in last place.

"It'll be nice to get to the break because of the grind," Nationals manager Manny Acta said. "We need to get better on offense and defense, and I believe we will as we start to get guys back. We went from one of the top two or three teams defensively to the bottom because of injuries."

Wigginton's one-out homer, his eighth of the season, started the scoring in the second inning. Houston tacked on two more runs in the third with a rally Backe started with a double.

Darin Erstad's ground out moved Backe to third, and after Kaz Matsui struck out, Berkman punched a single to center to plate the run. Berkman then continued his career-best base-stealing season by swiping his 15th bag. His previous career high was nine (2004).

Lee followed with another single to center as Berkman raced home, giving the Astros a 3-0 lead.

Backe had to work out of a few early jams. In the second inning, Washington had the bases loaded with two outs, before Perez fanned to end the threat. Then in the third, a Paul Lo Duca single and Cristian Guzman walk put two runners on with two outs. Backe, though, got a fielder's choice grounder and strikeout to escape the inning and made the lead stick.

Then, in the seventh, Houston's offense added some insurance runs. Against Charlie Manning, Backe led off with a single and moved to second on a sacrifice. Matsui grounded out, but Berkman was intentionally walked and Jesus Colome came out of the bullpen to pitch.

However, Colome tossed a pitch away, and both runners moved into scoring position for Lee, whose single to right plated Backe and Berkman for a 5-0 edge.

Backe walked Willie Harris to begin the eighth, and was lifted for Chris Sampson, who was perfect over the final two frames to finish the game.