Washington has lost 15 games when the opponent has scored three runs or fewer. The Nationals have lost eight games in which the opponent has scored two or fewer runs. They’ve been shut out 11 times, including three losses by 1-0. The Nationals’ offense ranks second to last in the NL in average and hits and 12th in RBI and runs.

The most conspicuous offender is high-priced free agent signing Jayson Werth, who has four RBI since June 18 and is hitting .217 this season. In his two previous games before yesterday’s win, Werth grounded into a game-ending double play on Saturday, eliciting boos around the stadium, and struck out in the ninth on a pitch in the dirt on Friday.

“I think he’s right on the verge of busting out,” Manager Davey Johnson said of Werth, who hit two balls hard to left field in yesterday’s 2-0 victory over Colorado that ended a three-game slide. “He’s had some history of great second halves. I don’t worry about a guy like Jayson Werth.”

It’s not been just Werth though. Ryan Zimmerman has four home runs and 15 RBI in 33 games, although he’s less had less than a month back in the lineup after recovering from an abdominal surgery.

“Jayson and I haven’t done crap,” Zimmerman said.

The starting rotation, meantime, has far exceeded expectations, most notably with Jordan Zimmermann, surgically repaired arm and all, displaying the promise that made him Washington’s first phenom before Stephen Strasburg. Throw in John Lannan and Jason Marquis becoming reliable in the middle to back end of the rotation, and it’s easy to see why Washington’s team ERA is 3.53, good for sixth in the National League.

Zimmermann had his 14th quality start against the Rockies to salvage the final game of the series heading into the all-star break. He said his slider was the best it’s been in his career, and although he had plenty of energy remaining to work beyond his 6 1/3 innings, he had no issues with Manager Davey Johnson’s decision to remove him when he did.

“I feel great, and I feel like if I keep pitching the way I am and keep the team in ballgames that the quality starts are going to add up,” said Zimmermann, who’s pitched much better than his 6-7 record may suggest. “Just one of those streaks where I got on a little roll there, and everything was clicking for me.”

What’s really made a difference is the bullpen heading into the all-star break as one of the most reliable in the big leagues despite some recent overuse. All-star Tyler Clippard leads the majors in holds (23), and closer Drew Storen has converted 23 saves in 26 chances.

Then the Nationals have received boosts from the likes of Ross Detwiler, who was called up for a spot start last week and pitched two scoreless innings of relief on Friday after Lannan had to leave in the fifth when he got hit in the face by a ball.

“I think ending the first half on good note is really key,” Storen said. “Five-hundred is not where we want to end up, but I think that’s a big step forward from where we were at the beginning of the season, so I think it’s a good stepping stone to where we want to be.”