HOUSTON -- The Astros weren’t built to win just one championship. Raising the trophy one time was never going to be good enough. You don’t endure three consecutive years of losing 100 games to rebuild into a juggernaut and get just one taste of champagne at the end of October.

Perhaps that’s what drove the Astros to wash away last year’s heartbreaking playoff loss to the Red Sox and come roaring back to a club-record 107 wins. Maybe that’s why they remained laser-focused despite being tested by the Rays in the American League Division Series and never took anything for granted when they pushed the mighty Yankees to the brink of elimination in the AL Championship Series.

And when Yankees first baseman DJ LeMahieu hit a stunning two-run homer in the ninth inning of Game 6 of the ALCS to tie the game, that simply set the stage for José Altuve -- the only Astros player who endured the three 100-loss seasons in a row -- to send the Astros back to the World Series.

Altuve crushed an Aroldis Chapman slider and hit a towering walk-off two-run homer in the ninth inning to score George Springer for a 6-4 win over the Yankees in Game 6 on Saturday night at raucous Minute Maid Park. The Astros won the best-of-seven series, 4-2, to punch their ticket to the World Series for the second time in three seasons.

• Box score

“We're not going to the World Series because of me,” said Altuve, who was named the ALCS MVP after hitting .348 with two homers. “We're going to the World Series because of everybody inside of the clubhouse.“

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The Astros will play host to Game 1 of the World Series on Tuesday night at Minute Maid Park against the National League champion Washington Nationals, who overcame a 19-31 start to reach their first Fall Classic. Nearly eight months after the Astros and Nationals -- who share a Spring Training facility in West Palm Beach, Fla. -- began the season with an exhibition game, they will meet for the right to be called World Series champions.

“We’ve said all along our goal was to win multiple championships,” Astros president of baseball operations and general manager Jeff Luhnow said. “We’re not there yet.”

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It’s the third time in five seasons the Astros have eliminated the Yanks, who battled with Houston for the best record in baseball all season before losing home-field advantage in the final week of the regular season.

“I feel like we are on equal footing with them,” Yankees manager Aaron Boone said. “Unfortunately, sports can be a little bit cruel for the team that goes home and such can happen in the series.”

The Astros, who have been headlined all season by their star-studded starting pitching, had to turn to their bullpen to try to finish off the Yanks, saving dominant ace Gerrit Cole for a possible Game 7 -- and in a perfect world -- Game 1 of the World Series on Tuesday.

The start of the game couldn’t have gone any better, with Brad Peacock using seven pitches to breeze through the first inning. Needing a hero, Yuli Gurriel -- 1-for-20 in the ALCS entering the game -- blasted a three-run homer to left in the bottom of the inning to give the Astros a 3-0 lead. Gary Sánchez answered with an RBI single off Peacock in the second.

“It's nice when you take the lead, especially in an elimination game on the other side, it puts an immense amount of pressure on those guys,” Astros manager AJ Hinch said. “It wouldn't surprise me that Yuli was in the middle of it, because he's been mere feet away from being in the middle of virtually every good thing that's happened to us offensively in this series.”

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Now it was up to Houston’s bullpen. Could it hold the lead?

Ryan Pressly bailed Josh James out of a bases-loaded jam in the third but not before reinjuring the right knee that caused him to have surgery in August. Wide-eyed rookie Jose Urquidy allowed a solo homer to Gio Urshela in the fourth but managed to hold the lead through 2 2/3 innings.

“He was incredible tonight,” Hinch said of Urquidy. “What's hard for a young player is not really knowing what was going to happen or how he was going to be used. It probably would have been easier on him emotionally just to start the game and have the normal routine, and we weren't going to do that. And we told him we weren't sure if or when he was going to pitch, but the way the game was progressing and we went through a lot of pitching early, we don't win this game if Urquidy doesn't come in and get the outs that he did at the time in which he did to turn it over to the back end of the bullpen.”

Then there was steady veteran Will Harris, who got the final out in the sixth and three more big ones in the seventh, with an unreal assist from left fielder Michael Brantley. He made a diving catch of an Aaron Hicks fly ball and doubled up Aaron Judge at first to end the inning and make Minute Maid Park erupt with noise.

Joe Smith worked a scoreless eighth, getting another spectacular play -- an Altuve-to-Carlos Correa-to-Gurriel double play -- to end the inning, with Correa’s throw to first registering 94.5 mph by Statcast. Roberto Osuna gave up the two-run dinger to LeMahieu, but Houston’s bullpen day was a success.

“Our bullpen, we all read what everybody writes that everybody we face has a better bullpen than us and to do it on a bullpen day [was sweet],” Smith said. “It took everybody out there, though.”

From pitching to defense, the Astros were doing everything they had to do to overcome their offensive shortcomings in the series. They were two outs away from a tense win when LeMahieu socked his game-tying homer just over the glove of a leaping Springer. Minute Maid Park sat in stunned silence.

“I knew that was gone,” Osuna said. “That was a terrible feeling. I felt terrible. When Altuve hit the homer, obviously I came back to life and pretty excited right now.”

In the end, it worked out like it should have for the Astros. It was Altuve sending the rocket into the night. It was Altuve humbly rounding the bases and into a mass of teammates. It was Altuve that sent the Astros back to the Fall Classic.

“You make sure the ball is gone before you celebrate,” he said. “Then I'm thinking, ‘We're going to the World Series.’”