Nationals starter Dan Haren allowed five runs in five innings as Washington lost its fourth straight game and fell eight games behind Atlanta in the National League East. (Toni L. Sandys/THE WASHINGTON POST)

The sting stayed with Davey Johnson all day. In the morning, it repulsed him to tell hitting coach Rick Ecktsein that he had been fired. In the evening, he hoped the game — “the easy part,” he called it — would revitalize him. Johnson watched his Washington Nationals fall short in trying to erase a five-run deficit. As he slumped into his chair at his news conference after 10 p.m., he wore both kinds of pain of his ashen face.

“This is a bad day for me, you know?” he said. “I’m glad it’s over with.”

General Manager Mike Rizzo had fired Eckstein, a change meant to beget more change. For one night it produced only a somber layer on top of a numbing, 6-5 loss to the Pittsburgh Pirates. Jayson Werth’s second homer of the night, his fourth in two days, pulled the Nationals within one run in the ninth. But they could not overcome the deficit Dan Haren and a face-palm insurance run created, even after all-star Pirates closer Jason Grilli exited with forearm stiffness and left the final out — a grounder from Steve Lombardozzi — to Vin Mazzaro.

The Nationals’ fourth straight defeat and ninth in 11 games dropped them to 48-51, three games under .500 for the first time all season. With the Atlanta Braves’ victory in New York, the Nationals also tumbled a season-high eight games back in the NL East. All the losses, finally, claimed a victim in Eckstein.

“Obviously, the mood in the clubhouse isn’t very good,” Haren said. “This is a tough day for the organization. I don’t know if we’ve hit rock bottom. I don’t know the answer to that.”

For a moment, Nationals Park pulsed with an old feeling. Adam LaRoche, whose homer to lead off the fifth doubled as the first ball the Nationals hit out of the infield against Pirates starter Charlie Morton, drew a leadoff walk in the ninth. Up came Werth, who on Sunday smashed two homers off Clayton Kershaw.

Grilli left him a 94-mph fastball over the plate, and Werth crushed it to the opposite field. Once Werth walked into the dugout, he found Ian Desmond. They agreed, “the tide was turning a little bit,” Werth said later.

“Really, that’s the first time we had something going in a while,” Werth said. “It was a good feeling. Hopefully we get the job the done the next time.”

This time, Denard Span poked a double into the right field corner with one out. Wilson Ramos struck out, leaving the game to pinch-hitter Lombardozzi. Grilli threw him a fastball and grabbed his right elbow. Mazzaro jogged in from the bullpen. Three pitches later, Lombardozzi dribbled a slider to second base.

Werth’s homer could have forced extra innings if the eighth inning had not unraveled. Ian Krol, excellent since his midseason call-up, took over trying hold the Nationals’ deficit at 5-3. He yielded a leadoff single to Pedro Alvarez and left with two runners in scoring position and one out.

“I was just being too fine with my pitches,” Krol said. “I wasn’t going at batters like I normally do. It’s disappointing for me and the whole team. I kind of feel like I let everybody down.”

Johnson summoned Drew Storen to face Gaby Sanchez. He did the hard part and induced a shallow fly to left, moving within one out of escaping the jam. He needed only to retire No. 8 hitter Clint Barmes, who entered the night hitting .222.

In the sticky heat, Storen said he had difficult holding on the ball. He unfurled one fastball outside that bounced past catcher Wilson Ramos. A friendly bounce off the backstop held Alvarez at third. Given a reprieve, Storen yanked another fastball off to Ramos’s right.

“I’ve never seen that before with him,” Ramos said. “I don’t know what happened in that moment.”

This time, Alvarez bolted. Ramos scooped the ball off the brick wall and fired a throw to Storen, covering the plate. The ball arrived in time, but the ball hit Storen “right in the palm,” he said, and he could not hold on. Diaz signaled safe, and Storen put his hands on his head.

The play typified the Nationals’ night of small but meaningful miscues. In the fifth, pinch-hitter Roger Bernadina could have let Bryce Harper face a tiring Morton with the bases loaded. Instead, with two men on, he swung wildly at a 3-1 pitch off the plate inside. Having whiffed at ball four, he struck out on the next pitch.

“These games, there’s not a lot of margin for error,” Storen said. “And that’s what happens when you make mistakes. An opponent makes you pay for it. It’s time for us to start making people pay for their mistakes.”

The Pirates built their lead on two mistakes Haren made to Andrew McCutchen. He left a fastball up in the first and hung a slider in the third, and McCutchen crushed both for two-run homers. In his first 99 at-bats against Washington, McCutchen had 13 homers with a 1.488 on-base-plus-slugging percentage.

The blasts — which upped Haren’s league-leading total allowed to 21 — served as the basis of the 5-0 lead the Pirates took against Haren after the fourth.

“Kind of the story of my season,” Haren said. “Whenever I make a mistake, I pay the price for it.”

Monday afternoon, Johnson had drawn long, sad breaths as he discussed the Nationals’ dismissal of Eckstein. He gathered his players after batting practice and addressed the loss for “just a little minute,” Ramos said.

“I know everybody feels sad for Rick,” Ramos said. “But we’re on the field. We have to go out there and play hard. We can’t put those things together. We have to separate that.”

Monday, they blended together in a painful mix. The sting lasted all day for Johnson, and even as the day ended, it wasn’t clear when it may stop.