The Houston Astros are going back to the World Series.

In a classic battle that produced countless thrilling moments, the Astros ultimately prevailed in Game 6 of the American League Championship Series, defeating the New York Yankees 6-4 on Jose Altuve’s ninth-inning walk-off home run against Aroldis Chapman.

The drama was set up a half-inning earlier when DJ LeMahieu stunned Minute Maid Park by launching a game-tying two-run home run against Astros closer Roberto Osuna. It looked like Chapman would get New York right back in the dugout after he retired the first two batters in dominant fashion in the bottom of the ninth. Houston lead-off man George Springer drew a walk to keep the inning alive. Then Altuve yanked a 2-1 slider out to left field to set off the celebration.

A slugfest was anticipated with both teams relying on short spurts from back-end starting pitchers and full-time relievers. Excluding the ninth-inning power surge, that never fully developed, thanks to some stellar defense from the Astros and missed opportunities by both teams with runners in scoring position.

The Astros struck first when Yuli Gurriel launched a first-inning three-run home run against Yankees opener Chad Green. The Yankees started chipping away right away thanks to Gary Sanchez’s run-scoring single an inning later. New York then pulled to within 3-2 on Gio Urshela’s fourth-inning solo home run.

Houston added an insurance run in the sixth inning but left two additional runners in scoring position. That felt like a moment that could turn the tide in New York’s favor, but defensive gems from Josh Reddick, Michael Brantley, Jose Altuve and Carlos Correa helped keep Houston ahead until the ninth inning.

With their World Series ticket now punched, the Astros will look to bring home their second championship after winning it for the first time in 2017.

WHO MADE THE DIFFERENCE

• Jose Altuve: He might be the smallest player on the field, but time and time again Jose Altuve has come up the biggest when the Astros have needed him the most. That was the case again in Game 6 as he turned a potentially crushing ninth inning into a celebration with his 13th career postseason home run.

• DJ LeMahieu: You will not see a more remarkable at-bat than LeMahieu’s ninth-inning battle with Roberto Osuna. With the Yankees’ season on the line, LeMahieu fought off pitch after pitch before lining the tenth pitch for a home run. Had New York found a way to win this game, the at-bat would have reached legendary status in Yankees’ lore.

• Yuli Gurriel: Houston’s first baseman picked a good time to snap his slump. Gurriel was 1-for-20 in the ALCS before launching his first-inning three-run home run.

MUST-SEE MOMENT

Here are the three defense plays that made a big difference for Houston.

Left fielder Michael Brantley made the defensive play of the series when he dove to catch Aaron Hicks’ blooper and then doubled off Aaron Judge to end the seventh inning.

With the Yankees threatening one inning earlier, right fielder Josh Reddick sold out to catch Brett Gardner’s sinking line drive. If the ball gets past him, New York likely takes the lead. Instead, he squashed the rally.

In the eighth inning, Jose Altuve and Carlos Correa combined on a 4-6-3 double play that lit up Minute Maid Park and the radar gun thanks to Correa’s 94.5 mph throw.

WHAT THEY'LL BE TALKING ABOUT

It felt like the Yankees were playing a man or two short given the struggles of Edwin Encarnacion and Gary Sanchez. Encarnacion went 1 for 18 in the series with 11 strikeouts. Despite knocking in a run in Game 6, Sanchez went 2 for 19 with 11 strikeouts. Sanchez also struggled defensively, extending an Astros potential rally with a passed ball on a strikeout.

WHAT'S NEXT

The World Series will begin on Tuesday in Houston. First pitch for Game 1 is scheduled for 8:08 p.m. ET. The game will be broadcast on Fox.

The series is guaranteed to feature some elite pitching matchups as the Astros trio of Justin Verlander, Gerrit Cole and Zack Greinke will meet with Washington Nationals aces Max Scherzer, Stephen Strasburg and Patrick Corbin. The Nationals might actually have the edge with Anibal Sanchez also pitching well in October.

We're excited to see how this series plays out.

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