[4] Corbin allowed consecutive singles to second baseman Max Muncy and shortstop Corey Seager to start the fourth inning, although he kept Los Angeles from adding to its lead.

Against Los Angeles relievers Adam Kolarek, Kenta Maeda, and Joe Kelly, the Nationals offense managed only more hit, a double by shortstop Trea Turner in the ninth, their only base runner after the fourth inning;[5][4] the Dodgers pitching staff finished with a combined 13 strikeouts, giving up only three walks.

[8] With one out in the seventh, Nationals reliever Tanner Rainey – making the first postseason appearance of his career – walked pinch hitter Joc Pederson and gave up a single to third baseman Justin Turner.

[4] Fernando Rodney came in to relieve Rainey, walked Taylor to load the bases, and allowed a two-out single to Muncy that scored Bellinger and Turner and stretched the Dodgers′ lead to 4–0.

[9][10] Strasburg's 23-game postseason scoreless streak, which dated back to the 2014 National League Division Series,[9][10] finally came to an end in the sixth inning when Dodgers pinch hitter Matt Beaty singled, advanced to third on a double by right fielder Joc Pederson, and scored on a sacrifice fly by third baseman Justin Turner.

[9][10][11] With the Nats winning 3–1, Strasburg left the game after throwing 85 pitches[10] over six innings of three-hit, one-run ball, issuing no walks and striking out ten Dodgers.

[17] Not believing he could rely on his middle relievers to preserve close leads[14][16] – Washington's bullpen had finished the regular season with the worst ERA in the National League[16] – Martinez brought in starter Patrick Corbin to pitch what turned out to be the decisive sixth inning.

[15] Eleven Dodgers had come to the plate,[15] and Los Angeles became the first MLB team in history to score seven two-out, two-strike runs in a single postseason inning.

[14][15] Julio Urías relieved Kelly and faced pinch hitter Asdrúbal Cabrera, who hit a sacrifice fly that scored Soto from third but turned into a double play when Kendrick was thrown out trying to tag at second and reach third.

[14][15] In the ninth inning, however, Hunter Strickland came in to pitch and gave up two more runs to Los Angeles against the first two batters he faced, surrendering a single to Freese and a two-run homer to Martin.

[20][21] Left fielder Juan Soto walked to load the bases again before Kenta Maeda relieved Hill and got second baseman Howie Kendrick to ground out to end the inning.

[20][21] Finally tiring with one out in the seventh inning, Scherzer allowed a single to left fielder Matt Beaty and walked second baseman Gavin Lux and catcher Will Smith, but, with the bases loaded, he struck out pinch hitter Chris Taylor and induced a groundout by right fielder Joc Pederson – who narrowly missed a bases-clearing double or triple when he drove Scherzer's first pitch hard down the right field line, only to have it land about an inch (2.5 cm) foul[21] – to keep the Dodgers from scoring.

[20] Sean Doolittle and Daniel Hudson combined to pitch a scoreless final two innings for Washington,[20] and the Nationals won 6–1, evening the series at 2–2[21] and forcing a decisive Game 5 at Dodger Stadium two nights later.

[30][31] Strasburg continued to labor in the first, giving up a walk and a single before inducing shortstop Corey Seager to ground into an inning-ending double play without allowing Los Angeles to add to its lead.

[31] The Nationals mounted their first scoring threat in the fifth inning, when catcher Kurt Suzuki led off with a walk and center fielder Michael A. Taylor – starting for the third straight game in place of the injured Victor Robles – followed with a single that advanced Suzuki to second, but Buehler struck out Strasburg and shortstop Trea Turner and got right fielder Adam Eaton to fly out, keeping the Nats off the board.

Suzuki led off, and Buehler's fourth pitch ricocheted off his wrist and hit him in the face, a frightening turn of events that forced him to leave the game escorted by the Nationals′ training staff;[30][31] Yan Gomes came in to pinch run for him and took over the catching duties.

[29][31] Only the second postseason extra-inning grand slam in MLB history,[30][note 3] it gave the Nationals a 7–3 lead[30][31] and prompted Los Angeles fans to start heading for the exits.

[31] In the bottom of the 10th, Dodgers hitters faced Sean Doolittle, who pitched a perfect inning,[31] the game ending on a spectacular diving catch in shallow center field by Michael A. Taylor to retire Justin Turner for the third out.

[34][36][37] Washington's "Big Three" starters – Max Scherzer, Stephen Strasburg, and Patrick Corbin – had seen heavy use so far in the postseason, so Nationals manager Dave Martinez rested them and put No.

[42][44] Goldschmidt got no farther than first base, as Scherzer completed his outing by striking out left fielder Marcell Ozuna and getting catcher Yadier Molina to ground into an inning-ending double play.

[43] Sean Doolittle pitched the bottom of the eighth inning for Washington and gave up a two-out single to shortstop Paul DeJong, followed by a liner into center field by pinch hitter José Martínez.

[42][43] Daniel Hudson, who had returned to the team only seven hours earlier[38] after missing Game 1 to be present for the birth of his daughter in Phoenix, Arizona, got the final two outs and his third save of the 2019 postseason to secure a 3–1 Washington victory.

[50] Washington's starting pitchers had limited St. Louis to two runs and 11 hits and posted an ERA of 0.00 during the first three games of the series,[50] giving up three walks and striking out 28 Cardinals in 21+2⁄3 innings pitched.

[54] Robles singled on a ball to right field that fell into the grass between Wong, first baseman Paul Goldschmidt, and right fielder José Martínez when they failed to communicate about who would make the catch;[56] Soto scored on the play, and the other runners moved up.

[54] With the Nationals holding a 5–0 lead, St. Louis manager Mike Shildt took Hudson – who had thrown only 15 pitches[55][57] – out of the game and brought in starter Adam Wainwright in relief.

[54] Meanwhile, facing a long climb back to avoid elimination, the Cardinals′ offense began to put pressure on Corbin, reaching base for the first time in the third inning when Wong singled and Edman walked, although they did not score.

[54] After Cardinals reliever Andrew Miller retired all three Nationals he faced in the bottom of the eighth inning,[54] Daniel Hudson returned to the mound to pitch a perfect ninth.

The Astros threatened to tie the game in the eighth inning, when pinch hitter Kyle Tucker led off with a single, tagged and advanced to second on a fly out, and scored on a one-out Springer double that narrowly missed going over the fence[63] to reduce Washington's lead to one run.

In the seventh inning, Trea Turner was controversially called out for interference as home plate umpire Sam Holbrook ruled that he prevented first baseman Yuli Gurriel from cleanly catching a throw from Brad Peacock.

Although the call forced baserunner Yan Gomes to return to first base, Rendon picked up Turner by smashing a two-run home run to left field off reliever Will Harris, giving the Nationals a three-run lead.