Denver, CO (Best E Casino) - Wil Nieves and Willie Harris drove in two runs apiece to give the Washington Nationals a 6-3 victory over the Colorado Rockies, sweeping Thursday's doubleheader at Coors Field.

Odalis Perez (5-8) won his second consecutive start, throwing six solid innings on two runs and six hits. The southpaw struck out one and walked one en route to Washington's sixth win in seven games.

"We have new life, new energy," said Nationals manager Manny Acta. "These kids, for the most part, are playing good defense, and we're executing at the plate. Winning is contagious, so everyone around is feeling pretty high."

Lastings Milledge had two hits and a run batted in -- his fifth of the day -- and Emilio Bonifacio added an RBI for the Nationals.

Joel Hanrahan pitched a perfect ninth for his second save of the day and third of the season.

Ubaldo Jimenez (8-10) broke his streak of four consecutive wins, failing to record a quality start for the first time in eight starts dating back to June 27. The right-hander went only five innings, allowing six runs on eight hits while striking out four and walking six.

"For 18 innings, we couldn't catch a spark at the bat, then we couldn't get two clean starts," said Rockies manager Clint Hurdle. "We didn't do too much to help ourselves out today."

Garrett Atkins batted 3-for-4 with three RBI, including a two-run homer, while Troy Tulowitzki added two hits in Colorado's fourth defeat in six games.

The Rockies struck quickly in the first inning. With two outs, Matt Holliday worked a walk and Atkins followed with a home run, his 16th of the season, to give the Rockies a 2-0 lead.

The Nationals took the lead in the second with four two-out runs. Ryan Langerhans led off with a walk, and three batters later Perez singled. Bonifacio followed with an RBI single to right and Harris doubled home two more runs to give the Nats a 3-2 lead. After Ryan Zimmerman walked, Milledge singled to score Harris for the fourth run of the inning.

Jimenez got into a bit of trouble in the fifth, walking the first two batters, he faced. Two batters later with runners on second and third, Nieves doubled to center to knock in two and give Washington a 6-2 lead.

The Rockies got an unearned run in the seventh. With two outs, Holliday was safe at first on an error by Zimmerman. After stealing second, Atkins drove Holliday in with a single to left, cutting the deficit to three.

Game Notes

The Nationals lead the season series 2-1...The Rockies are 13-8 after the All- Star Break...Colorado begins a weekend series at home against the Padres on Friday while Washington plays a four-game set at Milwaukee...The loss was Jimenez's first since July 12 against the Mets...It was the Nationals' first doubleheader sweep since Sept. 2, 2006, against Arizona. The last time the Rockies were swept in a doubleheader was Aug. 19, 2004, against the New York Mets.