DETROIT -- Fernando Rodney stood in the grass just beyond the mound, his left arm outstretched toward the sky and his right arm rearing back, his signature bow-and-arrow celebration. He had just closed out a 3-1 Nationals victory over the Tigers on Friday night at Comerica Park, a win that put Washington over .500 for the first time since mid-April, at 41-40.

Consider how unlikely a scene this would have been even about a month ago. Rodney had been released by the A’s after a disastrous start to the season. In his last appearance for Oakland, on May 22, he failed to retire any of the four batters he faced as he allowed a pair of runs. At 42 years old, it was worth wondering whether his big league career was over. The Nationals, meanwhile, sunk to a season-low 12 games under .500 on May 23 (19-31) after being swept by the floundering Mets. More than a few wondered whether this Nats season was over.

And yet, there they were Friday night, Rodney celebrating after a spotless 1-2-3 ninth inning, notching a save with his ninth different club to tie a big league record with Octavio Dotel and Goose Gossage. And these Nationals have notched their fourth straight win.

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“It’s a lot of fun because we’ve come from the bottom,” said left fielder Juan Soto, who clubbed a 416-foot homer in the second inning. “So now we’re up here, and we’re feeling really good.”

Feeling good because Washington owns a winning record for the first time since April 18, when it was 9-8. It’s an accomplishment that seemed highly improbable when these Nationals were reeling.

After the sweep by the Mets, the job security of Nationals manager Dave Martinez was being questioned. Speculation ran wild about their approach to the July 31 Trade Deadline, and whether stars such as Anthony Rendon, Sean Doolittle or perhaps Max Scherzer could be available.

And then the Nationals got hot. They are 22-9 in their last 31 games, a winning percentage topped only by the Dodgers dating back to May 24. During that span, Washington has outscored opponents 188-130.

“I think it shows you the group we have in here,” first baseman Ryan Zimmerman said before the game. “It’s a huge credit to Davey [Martinez] and the rest of the coaches we have in here. It could’ve easily gotten negative, could’ve easily gotten away from the message that we said from Spring Training. ... I give Davey so much credit, last year and again this year, for never changing who he is and staying the same person.

“It’s cool to see the team win now. We’ve gotten back to .500 but we got to keep it going. There’s no moral victories in here.”

Indeed, the Nationals came into the season with their sights set on much higher goals. Getting back above .500 is nice, but now they are set up to make a charge toward postseason contention in the second half. Washington still trails first-place Atlanta by seven games in the National League East, but the NL Wild Card spots are within reach after Friday’s win brought the Nats to within 1 1/2 games of the leaders.

“The boys are playing well,” Martinez said. “There’s a lot of excitement going on right now.”

And after digging themselves out of this early season hole, the confidence in the Nationals clubhouse is growing.

Their lineup is dangerous and deep from top to bottom, setting up dancing lines in the dugout to celebrate home runs. Their starting pitching has remained their backbone -- Anibal Sanchez turned in another strong outing when he struck out eight in six innings of one-run ball on Friday. And their previously beleaguered bullpen has even been solid, able to pick up the slack on Friday, a night where Doolittle and Wander Suero were both unavailable from heavy recent workloads.

“[The] Nationals are [a] very good team,” Rodney said. “I got a chance to play here tonight and see how good this thing is. I came ready for something special.”