CHICAGO -- By now, the Nationals are used to the script that began playing out Sunday afternoon at Wrigley Field, the one where they build a lead only to hand it over to their bullpen and watch it evaporate in the late innings.

Earlier in the season that recipe would have likely resulted in a loss, but these Nationals have flipped the script on their season. After blowing the lead in the eighth inning to send the game into extra innings, the Nationals rallied for a pair of runs in the 11th, beating the Cubs, 7-5, to complete a three-game sweep.

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It was the fifth win in a row for Washington and one of its most impressive victories of the year, sweeping a series at Wrigley Field for the first time since 2005. The Nats have won 12 of their last 14 games to build a four-game cushion for the top National League Wild Card slot.

“Resilient,” manager Dave Martinez said as he fought back some emotions after the game. “They’re very resilient. I’m telling you, I’ve said this all along: They’re not going to quit. That’s who they are.”

They did not quit when they were 19-31 on May 24, their season spiraling out of control early. Since then, they are 54-26 and percentage points ahead of the Dodgers for the best record in MLB during that span. It’s been the best 80-game stretch in club history.

With each day and win, these Nationals are starting to look destined for October, and once they get there they could be one of the most formidable teams in the National League.

“It’s been a lot of fun,” Martinez said. “And I credit these guys for sticking with it, ‘cause they could’ve easily gone south when things were going bad. But they didn’t. It’s a testament to the veterans, to the coaching staff, myself, [general manager Mike Rizzo], just constantly staying positive and bringing energy every day with these guys. They bring energy every day. We’re on a great run, and it’s been fun.”

Weathering a storm as big as that sluggish start makes comebacks from blown leads in the eighth inning seem easy by comparison. The Nats took a three-run lead in the seventh, only to watch Hunter Strickland give up a solo homer in the seventh and then Fernando Rodney yield a two-run homer in the eighth -- knotting the game at 5, where it would remain until extras.

This Nats’ offense has been so red-hot lately that it has helped lessen the absence of closer Sean Doolittle, who remains on the injured list with right knee tendinitis. And it was the offense that picked the team up once again on Sunday, plating a pair of runs in the 11th on a wild pitch from Tyler Chatwood and an RBI single from Anthony Rendon, who went 4-for-5 with a homer to extend his hitting streak to 12 games.

“Our pitchers are going to pick us up a lot of times, in games when we score no runs or maybe one run,” Rendon said. “But it’s our job as hitters, as position players, to pick up our pitchers as well. It’s not necessarily one-sided. Our defense has to pick up our pitching, and our pitching has to pick up our offense.”

Once the Nationals took the lead in the top of the 11th, Martinez had a conversation with Daniel Hudson, who had just completed a 10-pitch 10th inning, about returning to the mound. Hudson obliged and navigated the heart of the Cubs lineup, retiring all six batters he faced in extra innings to seal one of the club’s most impressive wins and series of the season.

“They feel like they’re never out of any game,” Martinez said. “And that’s the attitude we have. I can tell you now, the attitude I instill is: ‘This game is not over until the last out. Keep playing hard. Anything can happen.’”