Boos rained down on Gary Sanchez as he took the lonely walk back to the dugout in the sixth inning Tuesday night.

The Yankees catcher had just struck out for the second straight at-bat, and by the end of his 0-for-4 night, he had fallen even deeper into his postseason slump in a 4-1 loss to the Astros in Game 3 of the ALCS at Yankee Stadium.

Sanchez has gone missing, to the tune of 2-for-21 with 10 strikeouts and three walks in these playoffs, failing to provide any kind of offense for a team in need of it against the stud pitching of the Astros. He was 1-for-8 with three walks in the Yankees’ ALDS sweep of the Twins, but with a thriving lineup around him, it didn’t register as a pressing issue.

Now, Sanchez’s woes have entered the spotlight as one of the main culprits in a quiet offense.

“Every at-bat I’m battling,” Sanchez said through an interpreter. “I’m trying to make adjustments. I’m fighting to get back on track.”

Sanchez struck out twice against Gerrit Cole after popping up into foul territory in his first at-bat. He later grounded out to shortstop in his final at-bat against Will Harris.

“I definitely felt better at the plate,” Sanchez said. “I haven’t got the results I wanted, but I’ve been working hard, trying to get back on track. I’ll keep working.”

As if Sanchez’s bat wasn’t frustrating Yankees fans enough, his defense came into play in the top of the seventh inning. With the bases loaded and one out, Zack Britton threw back-to-back sinkers in the dirt to Yuli Gurriel. The first one got past Sanchez, but didn’t go far thanks to a deflection from home plate umpire Kerwin Danley. The second one evaded Sanchez’s blocking again and went all the way to the backstop, allowing Jose Altuve to score from third base for the 3-0 Astros lead.

“Throughout the whole season, I’ve been able to block those consistently,” Sanchez said. “Unfortunately tonight, I wasn’t able to.”

The 26-year-old Sanchez, who is now batting .174 (16-for-92) in 24 career playoff games, has hit seventh in all but one game this October (he hit sixth in Sunday’s Game 2). But manager Aaron Boone said he had no plans to replace him with Austin Romine.

“I’m seeing Gary miss some pitches,” Boone said. “I felt like he got another good one to hit today and put it on the net again. He’s got to take advantage of — especially when you’re facing a team like this with pitching like they have, when you do get a ball that you can handle, you’ve got to make sure it gets in play with authority and not on the net.”

— Additional reporting by Joel Sherman