WASHINGTON -- Sean Doolittle could see players on both teams getting fatigued toward the end of the nightcap of Wednesday’s doubleheader at Nationals Park between the Nationals and Rockies. The swings got longer as popups and strikeouts grew more frequent. The grind of two games in one day makes it difficult for any team to take both games of a doubleheader, making what the Nationals’ pulled off Wednesday that much more impressive.

Washington won both games of Wednesday’s split-doubleheader at Nationals Park, beating Colorado 2-0 after waiting out a one-hour, 41-minute rain delay in the nightcap to sweep their fourth consecutive twin bill, becoming the first team to do so since Cleveland from 2003-06.

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The win also brought the Nationals to within four games of the National League East-leading Braves, the closest Washington has been to first place in the division since May 4.

“Just continue to keep it going,” said Patrick Corbin, who tossed six shutout innings with seven strikeouts. “There’s something special going on in this clubhouse. We feel no matter who were playing everyday we come in here we have a good chance to win.”

That feeling is a stark contrast from where the Nationals once stood earlier this season.

Through the first 50 games of the year, Washington went 19-31 and stood on the cusp of being the biggest disappointment in baseball. And then from May 24 -- the low and turning point of their season after a four-game sweep at Citi Field -- through a victory earlier in the day, the Nats matched their best 50-game stretch in franchise history at 35-15. It equaled a 50-game stretch from both the 2012 and ’14 seasons, the first two division title winners in club history.

“Being able to come back after a tough start, I think, helps, because now it takes a lot of pressure off because every game doesn’t feel like a must win game,” Doolittle said. “If we do drop one, it’s not the end of the world. In May, there were some days, specifically in that [Mets] series, where it felt like the sky was falling after we would drop another tough game.

“And now, it seems like there’s so much to be said for a team finding a way to win. … I’ve talked about it before -- when a game is kind of hanging in the balance in the middle innings, we’re finding ways to extend leads, push runs across. We’re getting shutdown innings out of the bullpen. We’re doing such a better job of picking each other up and playing as a team.”

These Nationals are now playing with confidence as they begin their final stretch of the season, the final 62 game stretch that began with a victory in the nightcap Wednesday. They command the top Wild Card spot in the NL and all but buried the Rockies this week, pushing Colorado to 7 1/2 games behind a Wild Card spot. Earlier in the week, manager Dave Martinez spoke about how he would line Max Scherzer up to pitch a potential NL Wild Card game.

Martinez then quickly followed it up with his hopes that Nats are not in the Wild Card game because they still have not taken their eyes off the division, especially with nine games remaining against the division-leading Braves, including a three-game series next week at Nationals Park.

“A lot of people wrote us off,” third baseman Anthony Rendon said between games on Wednesday. “And said we need to make moves already or we need to do this, we need to do that, but you don’t win the division, you don’t win the pennant or whatever you want to call it in the first 50 games of the season or first 100 games of the season.”

So what to make of these Nationals? Are they closer to the team from the first 50 games or the team from the previous 50?

They will need reinforcements for this final stretch, particularly in the bullpen, but on Wednesday night, they continued to build on one of the best stretches in team history.

“Things are going our way now,” said catcher Yan Gomes, who hit a solo home run in the seventh inning of Game 2. “We know the kind of team we have, we know the kind of pitching staff we have. We’re rolling now. We really feel like that first half of the year, it’s so far behind us we’re not even thinking about that.”