George Springer fell down 0-2 in the count to start the night, but fought back and was walked by Joe Ross to start the night. Jose Altuve hit into a double play to erase the lead-off walk. Michael Brantley grounded out into the shift to end the top of the first.
Gerrit Cole followed Ross' footsteps and had a one-two-three inning of his own, striking out Trea Turner and forcing pop-outs to center field from Adam Eaton and Anthony Rendon.
Yuli Gurriel hit a single to start the second, and Yordan Alvarez finally broke out of his postseason slump with a two-run bomb to center, giving the Astros a 2-0 lead early.
Juan Soto hit a line-drive single that just went over Gurriel's glove to put the lead-off man on base for the Nationals in the bottom of the second. Howie Kendrick proceeded with a single as well that sent Soto to third with 0 outs.
Cole was able to force a double play that ended the second inning with no runs surrendered.
Altuve hit a blooper over second base with two outs in the top of the third, but nothing came out of it with a fly-out from Brantley.
Alvarez reached base for the second time with a line-drive single to right field in the top of the fourth. A wild pitch during Carlos Correa's at-bat sent Alvarez to second, and Correa proceeded to blast one to left field that put the Astros up 4-0.
In the bottom of the fourth, Cole walked a batter for the first time Sunday, which sent Rendon to first. Soto made great contact that excited Nationals park, but the line drive went directly to Springer in centerfield. Cole forced Kendrick to ground into a force out that sent the night to the fifth inning.
Through four innings, Cole had only surrendered two hits and struck out four.
Springer was walked again in the top of fifth with one out, sending Altuve to the plate. Altuve grounded into a double play to send the game to the bottom of the fifth with the score remaining 4-0, Astros.
It only took Cole six pitches to get through the fifth inning, and he seemed to be locked in for what could be his final start with the Astros.
Tanner Rainey replaced Ross in the top of the sixth. Ross finished his night giving up four runs on the two home runs from Gurriel and Correa. Brantley and Alex Bregman both sent balls to the warning track in the field, just short of home runs that resulted in outs. Another pop-out from Gurriel concluded the top of the sixth.
Gurriel had yet another highlight play in the bottom of the sixth. Turner hit a hard ground ball to first and Gurriel was able to snag it and dive to touch first base just before Turner's foot reached. Cole ran over in case he needed to cover first base, but Gurriel didn't need the help.
Sean Doolittle replaced Rainey in the top of the seventh, and Alvarez reached base for the third time Sunday with a ground-ball single to right field. Jake Marisnick pinch-ran for Alvarez and moved to center field.
Right after the Alvarez single, Correa grounded into a double play on the first pitch of the at-bat.
In the bottom of the seventh, Cole surrendered a home run to Soto that Marisnick just barely missed as he attempted to rob it in center field. It cut the Astros lead to 4-1.
The Nationals seemed to be gaining some momentum after Cole walked Ryan Zimmerman. With the 3-2 count to Victor Robles, the ump called a strike on what appeared to be a ball. Some felt it was a make-up call for a missed strike call earlier. The Nationals Park crowd was irate and let the umpire hear it after the strike call.
Springer started the top of the eighth with a double to right field, and Daniel Hudson opted to intentionally walk Brantley and Bregman was up to bat with two on and one out.
Gurriel sent Springer home with an RBI single on a grounder that barely got past Turner at shortstop, extending the Astros' lead to 5-1. Marisnick struck out with two on base that sent the night to the bottom of the eighth.
Joe Smith replaced Cole in the eighth, and Cole finished the night with seven innings pitched, three hits, one earned run and nine strikeouts in what was potentially his final start as an Astro.
Yan Gomes hit a lead-off single off Smith, but Smith redeemed himself with a strikeout to Asdrubal Cabrera and two more outs in another dominant relief performance.
Correa nearly extended the lead to 6-1 in the ninth, but was just inches off a home run to center field. Martin Maldonado singled on a line drive to left field that sent Kyle Tucker to the plate with one out and one on, but Tucker struck out.
Springer put the final dagger in Game 5 with an absolute bomb to left field that put the Astros up 7-1. According to ESPN Stats & Info, his seven home runs through a player's first 12 World Series games are tied for the most with Chase Utley.
Correa and Springer both homered in a playoff game for the seventh time, the most of any pair of teammates, according to ESPN Stats & Info.
Ryan Pressly entered to close it out for the Astros in the bottom of the ninth.