The Nationals' Wilson Ramos celebrates after hitting a game-winning single in the bottom of the 11th inning against the Braves. (Alex Brandon/Associated Press)

A dejected Stephen Strasburg walked off the mound in the third inning of the Washington Nationals’ 5-4 win over the Atlanta Braves on Wednesday night with his black glove over his mouth. His first start following a three-week stint on the disabled list abruptly ended after 42 pitches because he felt a pinch in the back of his right elbow. A stunned silence hung over Nationals Park.

In the long term, the Nationals’ World Series hopes, so promising exactly one month before Game 1 of the National League Division Series, had suddenly dimmed with Strasburg’s premature exit. How dim may be determined Thursday, when he is scheduled to undergo an MRI exam.

In the short term, the Nationals needed to scramble to figure out a way to win a game after getting 2 1/3 innings from their starting pitcher. A few hours later, a mob surrounded Wilson Ramos, his recent struggles forgotten, after the catcher’s walk-off single in the 11th inning off Braves left-hander Jed Bradley, which clinched the club’s fifth straight winning season and concluded an emotional night in the wee hours Thursday morning.

A night after using six relievers, the Nationals needed nine to get 26 outs and a couple hits from a couple players that carried them for much of the season to pick the bullpen up when it stumbled.

“We used guys we hadn’t used very much in the past out of necessity,” Nationals Manager Dusty Baker said. “They came through.”

Stephen Strasburg talks with trainer Paul Lessard, right, and teammates before leaving the game in the third inning. (John McDonnell/The Washington Post)

Baker chose left-hander Sean Burnett out of the bullpen first to face the left-handed hitting Ender Inciarte. In his fourth appearance with Washington this season, Burnett instantly squandered the lead by surrendering back-to-back doubles to Inciarte and Adonis Garcia before getting the final two outs.

Baker then inserted top prospect Lucas Giolito, a starter, to make his first career relief outing in the fourth frame. The tall right-hander, who was ready to pitch because he was on his regular rest, logged 3 1/3 innings and allowed two runs, one each in the sixth and seventh, to give Atlanta a 3-1 edge.

“The biggest thing is just kind of moving that pregame routine into during the game,” Giolito said. “Making sure you’re ready to go at any point, even though you may or may not get the call to come into the game. Just stretching out, being ready, getting enough throws in the pen.”

In the meantime, Braves right-hander Mike Foltynewicz was silencing the Nationals’ lineup. His only blip over six innings was Werth’s two-out RBI single on the 10th pitch of the at-bat in the second inning. Washington was held scoreless otherwise. Foltynewicz, whose fastball touched 98 mph, scattered five hits, struck out eight and walked three.

Washington promptly feasted on his replacement in the seventh. Stephen Drew, activated off the disabled list earlier in the day, led the inning off against right-hander Chris Withrow with a four-pitch walk in his first major-league plate appearance since July 23. Trea Turner followed with a single to reach base for the third time - the 27th game he has reached base more than once in 47 starts - and Werth singled to left field to load the bases for Murphy and chase Withrow.

The second baseman welcomed former Nationals left-hander Ian Krol with a line-drive single to left field that scored Drew and Turner. The plated runs hiked Murphy’s RBI total to 100. It is the first 100-RBI campaign of his career and the sixth in Nationals history.

Washington’s bullpen held until the 10th inning. After the southpaw Oliver Perez did his job by inducing a groundout from the dangerous Freddie Freeman, Baker elected to bring in rookie Trevor Gott for his second appearance. Gott began by striking Matt Kemp out swinging through a 95-mph fastball. Then, with two outs, he encountered trouble. First, Nick Markakis cracked a double. Next, he walked Tyler Flowers. Jace Peterson then singled to bring home Markakis.

With reliever Jim Johnson on deck, Gott intentionally walked Dansby Swanson. The strategy worked: The Braves didn’t pinch-hit for Johnson, the club’s closer, and essentially gave the at-bat away because Johnson struck out on three pitches to strand the two runners.

The idea was to have Johnson seal the game in a save situation in the bottom half of the frame. The plan flopped. After getting Ryan Zimmerman to strike out for the fourth time, Johnson yielded singles in succession to Danny Espinosa, pinch hitter Chris Heisey, and Anthony Rendon, who had entered the game as a pinch runner in the eighth inning, to fumble the lead away. Matt Grace and Mat Latos then combined to pitch a scoreless 11th inning. Latos, another starter by trade, got his first win in a Nationals uniform in his second appearance.

The first four pitches Strasburg threw in the third inning, to Swanson, did not signal trouble, though Swanson smacked the fourth, a 96-mph fastball, into the right-field corner for a double. But Strasburg displayed discomfort three pitches later, after throwing an 88-mph slider to Foltynewicz. Strasburg then uncorked a wild 92-mph fastball and winced immediately. He clenched his right fist and winced some more, peering into the Nationals’ dugout as to convey something wasn’t right.

In discernible pain, he circled around the mound and stepped on the rubber to throw an 84-mph slider over the plate that Foltynewicz fouled off trying to bunt for his fifth strikeout. After tossing the pitch, Strasburg grimaced and pounded his glove with his eyes towards the Nationals’ dugout again. The repeated body language coaxed trainer Paul Lessard and Mike Maddux out onto the field as infielders circled the Nationals’ prized hurler.

“And then they called me out,” said Baker said. “That was a long walk.”

At the moment, Strasburg was the concern and he will remain so in the coming days. But they had a game to play Wednesday and a few minutes before 1 a.m., Ramos and his teammates were celebrating a victory, a welcome diversion from the uncertain future facing their $175 million right-hander.

“It’s exciting on one hand because we won,” Ramos said. “But also it was a sad moment because we need Stephen and with what happened we know we’re going lose him for some time.”