Danny Espinosa appears comfortable in his new role as leadoff hitter in the Nationals' lineup.

Espinosa, who was moved into the No. 1 spot before Friday's series opener, followed up a three-run homer in the opening game with a bases-loaded triple in the seventh inning of the second game that helped the Washington Nationals to a 5-1 victory Sunday and a doubleheader sweep.

In the opener, Ivan Rodriguez also hit a three-run homer and Jason Marquis pitched into the eighth inning of the Nationals' 8-4 victory.

"It was great to get this sweep," said Espinosa, had six RBIs in the doubleheader and seven in the three-game series sweep. "After we got the first game, we knew in here, we were talking, 'We need to get that sweep. We need this game.' And we went out there and played hard and things went our way."

Several Nationals who had been slumping had big days at the plate.

Jerry Hairston entered with one single in 23 at-bats this season. He homered, doubled and singled for the Nationals in the nightcap. Shortstop Ian Desmond, who was bumped out of the leadoff spot by Espinosa, started the season 0 for 29 at home before his sixth-inning double in the first game. Desmond hit his second homer of the season two innings later.

Washington had five home runs in the doubleheader, and set season bests with eight runs and 11 hits in the opener. The offensive show was a welcome sight for the Nationals, who entered the day last in the National League in both batting average and slugging percentage.

"We've got a lot of veteran guys, and we've tried to tell the young guys, 'Don't panic,'" Hairston said. "It's two weeks. Six, seven, eight, 15 games is nothing over the course of a long season."

Saturday's game was postponed by rain, leading to the first doubleheader at Nationals Park since a twin-bill with the Giants on June 4, 2009. It was the second doubleheader sweep for the Nationals since moving to Washington before the 2005 season. Their first came Aug. 7, 2008, at Colorado.

Washington's starting pitching was as good as its offense Sunday.

Marquis (1-0) allowed two runs and nine hits in seven-plus innings. He struck out four and walked one. It was Marquis' first home win in eight tries with the Nationals.

His only real problems came in the fourth, when Milwaukee loaded the bases on singles by Casey McGehee, Mark Kotsay and Carlos Gomez. The Brewers' starting pitcher, Yovani Gallardo, came up with one out and singled to right field, scoring McGehee and giving Milwaukee a 2-0 lead. Marquis got out of the jam by retiring Rickie Weeks on a foul popup and getting Craig Counsell to ground out to short.

Gallardo (1-1) allowed seven runs on 10 hits, striking out five without a walk. McGehee was 3 for 5 with an RBI for the Brewers.

In the second game, Livan Hernandez (2-1) allowed one run and six hits in seven innings. He struck out three and did not walk a batter. Hernandez retired the first eight men he faced in his longest outing this season.

"Anytime you get a doubleheader you get a little nervous about that pen," said Adam LaRoche, who hit a home run in the eighth inning of the second game. "It was big for Jason and Livan to go as deep as they did and really save some guys down there. They were phenomenal."

Milwaukee's Kameron Loe (1-1) was the loser in the second game. He gave up singles to the first three men he faced, and then Espinosa cleared the bases with his one-out triple to give the Nationals a 4-1 lead.

"I don't think anybody was lacking confidence," Washington manager Jim Riggleman said. "But I think our position players have to feel real good about what they're seeing from our pitchers, and realize that once we get it going we're going to be pretty good. The sooner the better, and we did get it going this whole series."

NOTES: Washington placed RHP Todd Coffey on the 15-day disabled list (left calf strain) retroactive to April 9 and recalled RHP Collin Balester from Triple-A Syracuse. ... The Nationals starting pitcher has lasted at least five innings in every game this season. ... Milwaukee OF Nyjer Morgan (right thigh bruise) did not start in either game. Morgan, who was traded to the Brewers from the Nationals in March, grounded out as a pinch-hitter in the seventh inning of the opener. ... Brewers RHP Zack Greinke (fractured left rib) will travel with the team to Philadelphia, and then leave to make his first rehab start for Class-A Brevard County on Tuesday. ... Brewers OF Ryan Braun has reached base in all 15 games this season. ... Nationals OF Jayson Werth was rested in the second game, the first time this season he did not play.