He has the corner locker in the locker room, and he gets along as easily with his new Giants teammates as he did with his old Jets teammates. He is no longer the mane man with the wild hair sprouting everywhere. He is the discarded enigma who failed to live up to the great expectations of the franchise that expected him to be a star.

And now Leonard Williams looks to sack that second contract the Jets decided he was not worth giving and simultaneously prove Dave Gettleman right when too many Giants fans fear that their general manager’s plan is all wrong.

There is much to like about Leonard Williams: good guy, good teammate, good player. Except being the sixth-overall pick of the NFL draft can be a curse, because the sixth-overall pick is supposed to make the impact that Jamal Adams is making now for the Jets, that Quenton Nelson is making for the Colts, that Ronnie Stanley is making for the Ravens, that Daniel Jones is making for the Giants.

Of course, just because he has not panned out to be J.J. Watt doesn’t mean anyone should be calling Williams a bust. He is strong, athletic and durable and no one pushes him around at the point of attack. They called him Big Cat at USC for a reason. And he is only 25 years old.

Gettleman, with his Hog Mollie obsession, was seduced enough either by what Williams is or what he can become to fork over a third-round draft pick and a fifth-round pick that could become a fourth-rounder should Williams sign a deal that figures to approach $12-13 million per.

Lost in translation is what happens, pray tell, if there is a coaching change and the new staff isn’t sold on Williams?

In the meantime, the burden of proof rests on Williams to give the Giants more bang for their buck than he gave the Jets, to show that he can be one of those classic late bloomers whose best football is ahead of him.

In other words, prove the Jets wrong and prove the Giants right.

No one should be expecting Michael Strahan here, or Osi Umenyiora, or Justin Tuck. It may very well require lining up alongside Chase Young, if Gettleman is so fortunate, to unleash the quarterback predator within Leonard Williams. If there is one. The Jets never could find an edge rusher who could free Williams to do more than the dirty work.

It will stamp Williams when his career is done as an underachiever should seven sacks stand as his single-season high given his physical gifts.

It speaks to Williams’ character that he has been dedicated to doing his job within the confines of the Jets defense and earning the praises of his coaches.

It didn’t stop the Jets from giving up on him.

It didn’t stop Gettleman from making a Lambeau leap of faith.

Giants fans who are bemoaning the fact he traded away what will be a pick at the top of the third round are struggling to make a similar leap of faith in Gettleman, their GM with a 7-20 overall record.

If there is even a hint of latent greatness inside Leonard Williams, who was considered by some as the best player in the 2015 NFL draft, this would be the perfect time for him to unearth it.

He should do himself a favor and take a cue from Saquon Barkley, who told us, “The great ones figure it out.” Barkley refuses to see himself as anything but great and chases greatness every waking hour and won’t stop until he captures it. He demands it of himself. Williams should demand more of himself.

Williams did not hit the ground running as a rookie the way Barkley did, and has certainly not announced himself since as anyone’s Gold Jacket Guy. But Gettleman didn’t trade those draft picks not to try to sign him, because he’ll look like a fool if he doesn’t.

Marty Lyons was never a double-digit sacker, but fashioned an 11-year Ring of Honor career with the Jets. Williams might have enjoyed a similar career had he been able to stay, and perhaps would have been appreciated more for it over time. Perhaps. For what it’s worth, Lyons was the 14th pick in the 1979 NFL draft.

But the historic first trade between the Giants and Jets means the bar, fairly or unfairly, has been raised for Williams.

“He’s a force to be reckoned with,” Antoine Bethea told The Post. “Definitely one of those guys that you love to have on your side.

“You want your interior guys to do interior things, so I think a lot of people get lost in the Aaron Donald thing. You want your interior guys to clog up that middle, push the pocket, so the guys on the edge get there and then get your second-level guys to be able to run free.”

Williams has no sacks, but has 14 quarterback pressures (combined sacks, quarterback hurries and quarterback hits) in his three games as a Giant. Or 14 quarterback pressures, but no sacks. He can be more of a leader with so many younger defensive teammates now in his midst. He has a team that wants him.

If he wants them, he should want to force them to make him an offer he can’t refuse.

Prove the Giants right, and prove the Jets wrong.