WASHINGTON -- It started as a fist pump, but eventually Wander Suero just started throwing his arms around in a state of frenzied, giddy excitement. He let out an exuberant yell on the mound and then pumped his fists some more.

Victor Robles had just made a sliding catch in right field, avoiding second baseman Brian Dozier as he charged into the outfield, taking away a bloop single from Dansby Swanson that could have tied the game and sealing, perhaps, the biggest win of the season for the surging Nationals. They beat the Braves, 4-3, on Friday night to increase their win streak to a season-high five in a row, securing a crucial victory for a team making its climb back into postseason contention.

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Washington realized it had a golden opportunity in front of it this week at Nationals Park, and so far the club is taking full advantage, winning the first four games against the Phillies and Braves to begin inching its way back into the National League East race. The Nats are now 18-7 in their past 25 games, picking themselves up from a season-low 12 games under .500 a month ago, to just one game under .500 (37-38) after this victory. Their .720 winning percentage over that span is second in the Majors, behind only the Dodgers.

“Things are just going our way,” reliever Trevor Rosenthal said. “We have a really talented team… I think just now things are starting to roll our way a little bit and things are clicking. Guys are continuing to execute in big spots. Hopefully we can keep it going and keep it right here. I think there’s a good chance we do.”

This was the kind of game the Nationals might not have won at the start of the year, when everything that could go wrong, did.

They fell behind 3-0 after the first three innings to the Braves and their newest starter, Dallas Keuchel. They required three scoreless innings from their bullpen with Sean Doolittle and Tanner Rainey unavailable after pitching in consecutive games. They went 2-for-15 with runners in scoring position. Judging by the way things were going early on for these Nats, Robles’ diving play in the ninth seemed more likely to drop and allow both runners to score.

“We’ve gotten better in certain areas and we’re making the team go out there and beat us,” said starter Stephen Strasburg, who allowed three runs in six innings. “Instead of going out there and, 'Man, we gave them that game.'”

The Nationals’ bullpen has been their biggest flaw all season long, a weakness ready to expose itself each time they began to make a run toward contention.

And Friday night was even more tricky for Nationals manager Dave Martinez to piece together the final outs of the game, knowing he needed to stay away from using his two most reliable relievers in Doolittle and Rainey. He had two more arms who had also endured heavy workloads of late, but both Javy Guerra and Suero told him they would be ready to pitch if called upon, and Martinez trusted them.

“We need them all,” Martinez said. “They proved it tonight.”

Guerra tossed a scoreless seventh inning. Tony Sipp, who had only pitched four times this month and owned a 5.02 ERA, struck out Freddie Freeman to start the eighth inning of a one-run game. And with two outs in the eighth and the tying run at second base, Rosenthal, who spent a month on a rehab assignment ironing out his mechanics, recorded his biggest out of the year, getting Austin Riley to ground out to Anthony Rendon at third base to stop the threat.

“I’ve been anxious to get into a game, and be in one where we win,” Rosenthal said. “To have the chance to contribute is icing on the cake.”

But there was still the issue of the ninth inning and locking down the win without one of the NL’s best closers. Suero has had issues this season pitching in back-to-back days -- his ERA was 9.00 in those instances and opponents had a .917 OPS -- but Martinez asked him if he could throw for a third straight day. When Suero responded yes, Martinez told him to be ready for the ninth, and the manager saw Suero’s eyes light up.

That explained the emotion on the mound for Suero, pitching his way out of the jam with an assist from Robles to secure his first career save.

“The confidence he's given me, especially lately in big situations despite my numbers not being where I'd like them to be, he keeps giving me the confidence,” Suero said through an interpreter. “So I'm definitely excited.”