Yes, it was preseason. It didn’t count. It won’t have any direct impact on the games that matter.

But Andre Cisco didn’t just shrug off the mistake. As a fifth-year veteran, he knows better than that.

The Jets’ new starting free safety emphasized the importance of fundamentals after practice on Wednesday. He mentioned, “No matter your level, you’re never beyond focusing on the basics. These are mental checks you have to make before each play begins. It serves as a great reminder during preseason games. Naturally, you want to eliminate such errors from your game, and it’s frustrating when they occur.”

The play he was referring to came early Saturday night against the Giants at MetLife Stadium.

Cisco experienced a setback when Russell Wilson completed a deep 80-yard pass to Beaux Collins, who managed to get behind him. Just two plays after, the Giants scored a touchdown.

This sequence set the pace for a dominant 31-12 defeat. Post-game, new head coach Aaron Glenn criticized the team’s “sloppy” and “undisciplined” play, with Cisco’s lapse highlighted as a critical error.

“That wasn’t indicative of who we are,” defensive coordinator Steve Wilks said. “You talk about Cisco, a routine assignment like that, he makes that play every day for us just staying in the post. As soon as he came off the field, he knew that.”

Cisco, speaking for the first time since the setback to the Giants, owned it.

“A good reminder of the cost of not doing your job,” said the 25-year-old defensive back, who spent the first four years of his career with the Jaguars. “As a safety, sometimes you feel like you’re more in position when the ball doesn’t come to you, or whatever the case might be. Just a reminder that every inch matters. It happens more often than you think, in terms of you being in the right position and taking [the play] away, and nobody gives you credit for it, and the one time you’re out of position you pay for it.

“We know it’s not a talent thing or an ability thing. … It’s more mentally just being focused.”

After losing Chuck Clark and Ashton Davis through free agency, the Jets are counting on Cisco stabilizing the safety position after signing him to a one-year, $8.5 million deal in the offseason.

A third-round pick out of Syracuse, he started 47 games over four years for Jacksonville and had eight interceptions.

Cisco actually rooted for the Jets growing up in Valley Stream, L.I., and is thrilled to get the opportunity to play for his hometown team.

“I love it, man,” he said. “It’s been a blessing. Outside of just being here, the team, the group of guys we got, the time I was able to come in, it feels like the right time.”

The only drawback is ticket requests. They have come pouring in for Week 1 against the Steelers.

“I appreciate that because I was in a place where I wasn’t from for a while,” he said. “So when people came, it was few and far between, in terms of how often they could come. But now I have people who can drive up any time.”