Michael Bourn of the Atlanta Braves drops this triple hit by Rick Ankiel of the Washington Nationals in the sixth inning. (Kevin C. Cox/Getty Images)

The Washington Nationals began a nine-game, 10-day trip on Monday that they would use to measure themselves against the National League East. Five games in, even after Stephen Strasburg blew a four-run lead Saturday afternoon, the construct has flipped. It is the division, perhaps, that needs to measure itself against the Nationals, their surging offense and their 19-year-old force of nature that does not come equipped with an off switch.

The Nationals’ bats thumped to life again in an 8-4 victory over the Atlanta Braves, clinching their second straight road series win against a division rival. Danny Espinosa drilled a three-run home run in the second. Bryce Harper highlighted the Nationals’ late rally with a missile of a solo home run. Tom Gorzelanny added three innings of scoreless relief to put a stranglehold on the game — and, for what it’s worth in late May, the NL East.

“To spank them in their home park, that’s big,” Manager Davey Johnson said. “Scoring seven runs a couple games in a row, I feel like I’m on vacation.”

During their first two days at Turner Field, the Nationals have turned an early-season showdown into a beat-down. They entered the weekend with a one-game lead, and as they head into their second “Sunday Night Baseball” showcase this month, the Nationals have pulled three games ahead of the Braves, with the Miami Marlins and New York Mets moving into a tie for second, 21 / 2 games out. Halfway through their late-May test, the Nationals are 4-1.

“It’s gets you good momentum,” Espinosa said. “It gets you confidence as a team to go out there and just play, have a feeling that we’re going to win. We’re feeling good. We’re hot. We can go out there and beat anybody.”

Washington Nationals center fielder Bryce Harper reaches for a ball hit for a two-run home run by Atlanta Braves' Dan Uggla (26) in the fifth inning. (John Bazemore/Associated Press)

The Nationals, whose offense sputtered through April, have scored at least five runs in five of their past seven games. Even before their 12-hit, two-homer outburst Saturday, they ranked fourth in the majors with a .452 slugging percentage in May.

The Nationals scored one run in the first inning after Espinosa, sporting bloomer-style pants with high socks, led off with a double against left-handed Braves starter Mike Minor. They added three more when Espinosa belted his fifth homer.

The Nationals still have an elite starting rotation, but they no longer rely on it. After Strasburg’s performance, they had to be thankful for that. Strasburg yielded four runs in five innings on six hits and four walks, the most he’s issued since the second start of his career.

“He’s usually picking us up,” Johnson said. “We picked him up today.”

After his last start, Strasburg said he felt fatigue in his arm. Over his last three outings, Strasburg has not recorded an out past the fifth inning and has allowed nine earned runs in 14 innings. His ERA rose to 2.64 Saturday.

“I just don’t think he had a good feel for his fastball,” Johnson said. “Sometimes, you get where you can’t locate with your main pitch. I’ve never seen it happen with him. But there’s nothing physically wrong with him.”

Strasburg regularly hit 97 mph and reached 99 with several fastballs. His change-up baffled the Braves, who swung at five of them for strikeouts. At his best, he still dominated.

Stephen Strasburg of the Washington Nationals pitches to the Atlanta Braves at Turner Field. (Kevin C. Cox/Getty Images)

But Strasburg often appeared uncomfortable. During one span, from the end of the third inning through the start of the fourth, Strasburg threw 18 balls in 24 pitches. His mechanics fell out of whack. He threw four straight change-ups to third baseman Juan Francisco.

“I tried one thing, and it wouldn’t work,” Strasburg said. “I tried another thing, and that wouldn’t work. It was just one of those days.”

Strasburg, for all his powers, is not invincible. The prime evidence is Dan Uggla, the sawed-off Braves second baseman with overgrown biceps, a wad of tobacco in his left cheek and a jersey one size too small.

Uggla entered the game 5 for 6 against Strasburg with a double, a home run and a walk. Strasburg’s competitiveness consumes him, and he had surely kept score. In his first at-bat, Strasburg threw Uggla two 99-mph fastballs and struck him out with a change-up. Strasburg would throw only two other pitches harder than 97 all day, both to the next batter.

Uggla drew a walk in the third inning. In the fifth, he came to the plate with two outs, the Braves down 4-2 and a man on second. Strasburg’s pitch count climbed above 90 as he fell behind in the count. On the 3-1 pitch, he fired a 94-mph fastball, thigh-high and down the middle. Uggla crushed it over the center field fence.

Strasburg stared out to the outfield as if trying to make sense of what happened. Uggla had improved his career line against Strasburg to 6 for 8 with two homers, a double and two walks. The Nationals’ four-run lead had vanished and become a 4-4 tie.

The Nationals immediately struck back. After Ian Desmond doubled to lead off the fifth, Chad Tracy delivered a pinch-hit double to left-center, putting the Nationals ahead for good at 5-4. Tracy left with a groin injury, and pinch-runner Edwin Jackson scored on Rick Ankiel’s two-out triple.

The Nationals were in control, and Harper added the finishing touch. He already had put his stamp on the game. In the fifth, he hit a routine single to right field. He sprinted out of the box and watched Jason Heyward nonchalantly field the ball, the kind of thing Harper dines out on. Harper bolted to second base, sliding in headfirst.

“When an outfielder doesn’t come up hard, I usually take the next bag,” Harper said. “I was on the way before he bobbled it. Once he bobbled it, I knew I was surely in there.”

The official scorer gave Heyward an error. “A good hustle double, that’s always fun,” Harper said. “Maybe they didn’t give it to me, but I thought it was. I like doing that.

Harper would be stranded at second. But against reliever Jonny Venters in the seventh, Harper would make sure no such problem happened again. Harper lined a 1-2, 94-mph sinker to left field. It nearly tore a hole in the wall that separates the fence and the fans.

“That was a rocket,” Johnson said. “That might have been the hardest ball hit to left in a while. He hit the heck out of that off a dang good pitcher.”

Harper had raised his averages to .278/.366/.495, another cog firing at full capacity for the Nationals. Afterward, Harper uttered something that, if true, is truly frightening for a division the Nationals have control of.

“It’s only a matter of time,” he said, “before I get going.”