Human nature is a force more powerful than the NFL’s strongest player.

Human nature has been fracturing losing locker rooms and pulling players apart since the inception of team sports.

The 0-4 Giants, one of the league’s four winless teams, are the most vulnerable to a fractured locker room because, unlike the other three, they were supposed to be a Super Bowl contender this year.

The 0-4 49ers, with a rookie general manager and head coach, are in a long-term rebuild. The 0-4 Browns, well, they stink every year. And the 0-4 Chargers, with a rookie head coach in tow, are bitter about their hasty move from San Diego to L.A., where nobody cares about them.

So it’s possible that the Giants’ greatest savior at the moment is the fact that they play the Chargers on Sunday at MetLife Stadium. It’s possible the nomadic Chargers could be just the elixir the Giants so desperately need as they try to find themselves — and their first win.

To borrow from the great Tom Petty, who died suddenly at age 66 on Monday: “Even the losers get lucky sometimes.’’

But what if the Giants don’t capitalize on that luck? What if they don’t defeat a Chargers team they’re supposed to beat at home?

Then what? Then their locker room, already a place occupied by confused players who are wondering how this has all gone so wrong so quickly, could be ready to crack.

That is human nature, after all.

Because of that, the veteran leaders inside the Giants locker room are on high alert for any signs of internal fracturing, and they should be.

“It’s definitely something that we’re concerned about,’’ linebacker Jonathan Casillas told The Post on Tuesday. “No one wants to be where we’re at right now, and it’s really hard to have 53 guys motivated when you haven’t won since last December [Jan. 1 actually].’’

The Giants, indeed, haven’t had a lot in the way of positive reinforcement in too long. By the time they take the field against the Chargers Sunday, it will have been 282 days since they won a game — their New Year’s Day win over the Redskins in the 2016 regular-season finale.

Four players remain on the Giants roster who were a part of the 2013 team that started the season 0-6, won five of the next six and finished 7-9 — Eli Manning, Jason Pierre-Paul, Justin Pugh and Zak DeOssie. That team, remarkably, avoided fracturing from within and remained close.

Asked on Tuesday if has any concern about this locker room fracturing, Manning told The Post, “I haven’t seen any symptoms of that.’’

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