NFL

Cullen Jenkins doubts Giants’ backbone: We fold too easy

Cullen Jenkins said the Giants’ unimpressive preseason — and three-year absence from the postseason — isn’t about talent. It’s about temperament.

The big defensive tackle bluntly admits the Giants have lacked a killer instinct, a problem they need to fix this season to return to the playoffs.

“We’ve got to make it happen. We’ve got to have that game-day intensity, that switch, drive, where we go out and we hit the field on game day, we take that level up another step higher,’’ Jenkins said Monday.

“A lot of times we come out, we practice well, we go through things, we’re where we need to be — and then we get into the game and we may freeze up a little bit, or we just don’t carry it over, when you should be going into the game and stepping it up a notch. We’ve got to learn as a team how to go into game day with more of a killer instinct.’’

The Giants have sputtered through three preseason games. They have lost four safeties to injury and Jason Pierre-Paul to a fireworks incident. Victor Cruz still hasn’t been cleared to practice. That’s a lot of speed bumps before even getting to the season opener, and Jenkins acknowledged they haven’t dealt with them as well as they should.

“If you’ve got confidence, you know you’re going to [have adversity],’’ Jenkins said. “This is the NFL. No one team is going to go out there and not have its fair share of adversity. That comes along with the game. And if you know that, then you know that it’s required that you have to be able to respond to it.

“That’s what we need to do a better job of, you know? When we get hit in the mouth or when we go through adversity, we don’t respond as well as we should.”

That doesn’t just apply to a 1-2 preseason that nobody will ever remember, but to three straight idle postseasons that unfortunately nobody can forget. A proud franchise that won its fourth Super Bowl — and eighth NFL title — after the 2011 season, the Giants haven’t reached the playoffs since. It’s a failure that galls them.

“They’ve got a lot of history, a lot of tradition, big winning tradition,’’ Jenkins said. “When you come here, that’s one of the things you expect to continue, continue winning, continue going to the playoffs.

“And when you’re not able to do it, you definitely feel like you’re letting down the fans, the organization. There’s an urgency because we’re trying to get back to what’s normal and what’s expected around here, and that’s winning.’’

And Jenkins — who arrived from NFC East rival Philadelphia on a three-year deal in 2013 — doesn’t think the Giants can prove anything about their Sunday intensity until the Sept. 13 season opener against the reigning division champion Cowboys.

“Going into the regular season, regardless of how we play against New England [in Thursday’s preseason finale], we’ve got to be able to step it up in the regular season and improve,’’ he said.