HOUSTON — Giancarlo Stanton made his impact on the ALDS mostly through seeing a lot of pitches.

That changed quickly in Game 1 of the ALCS as Stanton went deep with two outs in the top of the sixth in the Yankees’ 7-0 win over the Astros on Saturday night at Minute Maid Park.

Stanton started his night with a 107 mph infield single to short off Zack Greinke in the second, and after flying out to center in the fourth, came up against the Houston right-hander again in the sixth.

With two out, two batters after Gleyber Torres had given the Yankees a 2-0 lead with a solo homer, Stanton belted a long blast to right-center to make it 3-0.

It was Stanton’s second postseason homer. He also went deep in last year’s wild-card win over the Athletics in The Bronx.

Since then, he’d picked up singles and walks, but Friday, Stanton expressed confidence he was close to breaking out — even against an Astros pitching staff known for strikeouts.

“You’ve just got to look for a good pitch to hit,’’ Stanton said. “They’re going to give you a good pitch. But you may just get one.”

He made it count on Saturday.

“[That was] a big one where he leaned on one,’’ manager Aaron Boone said. “But that comes from a product of him really looking for a pitch and zoning it up well.”

And that isn’t by accident.

“In the playoffs, it’s really about not giving away at-bats,’’ Stanton said. “I’ve worked hard on trying to do that. And it’s been working.”

Part of Stanton’s mindset came from having gone through the postseason for the first time a year ago.

“I’m learning,’’ Stanton said. “I’m learning.’’

Stanton took a similar approach in his home run at-bat as he has for much of the postseason. After falling behind 0-2, he worked the count to 3-2, fouling off a pair of pitches in the process. And on the eighth pitch, he crushed a 91 mph four-seamer into the Astros’ bullpen.

“That’s obviously what you want,’’ Stanton said. “Keep pushing. If you’re not getting pitches to hit, keep the line moving.’’

It helps that he’s in a lineup filled with hitters with a similar mentality.

“It wears down pitchers,’’ Stanton said of the team’s approach. “They’re throwing their best stuff and [our hitters] aren’t even checking it.”

Stanton played just 18 games during the regular season — nine after returning from a right knee sprain suffered on June 25.

Though Stanton still hasn’t been a force for the Yankees this season, he continued to show signs he might not be done yet.