Ian Desmond, Michael Morse and the streaking Nationals are showing no signs of slowing down and will play 16 of 22 games before the all-star break at home. (Greg Fiume/Getty Images)

Go ahead, take a six-run lead against them. Hold them to a pair of runs. Heck, beat around their pitchers for 18 hits. Lately, none of it works against these Washington Nationals. They are baseball’s hottest team. They also are baseball’s most eclectic winners.

The Nationals stretched their winning streak to seven games Friday night with an 8-4 victory over the Baltimore Orioles before 35,562 at Nationals Park, their latest win with a steep degree of difficulty attached. The Orioles pounded 18 hits, including 12 off starter Jason Marquis, but the Nationals scored four runs in the fifth inning and another three in the sixth to match their longest winning streak since their 10-gamer in the summer of 2005.

Two more wins, and the Nationals will have reached a .500 record this late in the year for the first time since that inaugural season. There is no sign they are about to slow down, either. They’ve won all four games since Ryan Zimmerman returned to the lineup, all six since the pitcher started batting eighth. They’re 18-12 at home this season, and because of an inordinate amount of road games to open the season, they will play 16 of their 22 games before the all-star break at Nationals Park.

The difference between now and just three weeks ago revealed itself Friday night. Most games during April and May, they could not score more than four runs, and they allowed difficult situations to spiral.

“This game,” Manager Jim Riggleman said, “we had no chance earlier in the year.”

With Philadelphia’s loss at Seattle late Friday night, Washington had the longest winning streak in baseball.

Friday, they limited damage with runners on base. More importantly, they’re averaging more than six runs per game since Jayson Werth moved to leadoff and the pitcher’s spot, in defiance of convention, moved to eighth.

“I really think the lineup change has affected all of us,” shortstop Ian Desmond said. “I think a lot of the credit has got to been given to Riggleman and Jayson, for accepting it. That’s been really big for us. He’s been up there taking a lot of pitches to start the game. He’s really turning the lineup around nicely.”

The Nationals overcame the Orioles’ barrage — which included five hits by Derrek Lee and four apiece by Nick Markakis and Adam Jones — by stranding 12 runners. The 18 hits are the most allowed by the franchise in a win since its return to Washington.

The Nationals also benefited from another balanced offensive attack. Every starting position player reached base, Roger Bernadina putting the final touch on that by blasting a solo homer in the eighth. Jerry Hairston, recently displaced by the return of Zimmerman, went 3 for 3 with a walk and two doubles, the second of which scored Wilson Ramos with the go-ahead run in the sixth inning.

Desmond went 2 for 3 with a walk and provided a bit of everything. He shot an RBI single to center in the fifth that extended his hitting streak to 11 games, stole his 19th and 20th bases and scored a run on Zimmerman’s RBI single.

The Nationals’ robust attack looked like nothing after four innings, at which point they trailed, 2-0. Orioles rookie left-hander Zach Britton had shut them out and allowed one hit before Ramos led off with a single. Hairston ripped another single, and up came Marquis with the at-bat that turned the game.

With Ramos on third, Marquis dropped a sacrifice bunt down the third base line. Mark Reynolds charged, scooped the ball and checked to see if Ramos had strayed off the base. The glance may or may not have thrown Reynolds off, but he uncorked a throw that sailed about 15 feet to the right of first base.

“He looked up and saw Jason hustling down the line,” Hairston said. “He may have rushed the throw.”

Ramos scored, and the Nationals had runners on second and third with no outs. Bernadina drove in a run with a groundout, and the Nationals would bat around until they had turned a 2-0 deficit into a 4-2 lead.

Marquis, coming off a five-game suspension, could not pitch long enough for the win. He surrendered hits to two of the first three batters he faced in the sixth, the second a Robert Andino double that gave the Orioles their 12th hit. Riggleman summoned Todd Coffey, who let both runners score and turned it into a tie game.

Coffey handed the ball off to Sean Burnett with the bases loaded. One night after pitching a scoreless 10th, Burnett escaped with one pitch, a sinker that Matt Wieters slapped to third base.

“We dodged a lot of bullets tonight,” Riggleman said.

After Ramos walked and Hairston doubled him home for a 5-4 lead, Burnett’s night turned strange. He came to bat for the first time since 2009 and tried to lay down a bunt with Hairston on second. Reliever Jeremy Accardo wouldn’t let him. Burnett walked on four pitches. He then went first to third — with a nifty pop-up slide — on Werth’s single and scored the second run of his career on Desmond’s sacrifice fly.

“Believe me,” Hairston said. “He let us know. He was making a case to pinch-run.”

After their latest win, the Nationals could afford to joke with each other in their clubhouse. Lately, they don’t wonder if they’re going to win. Only how.