There are plenty of Giants fans salivating over the prospect of using the fourth-overall pick of the draft on the freak Swiss Army knife Isaiah Simmons.

Understandable on several levels:

He is a wondrous playmaker, a chess piece/toy and every defensive coordinator’s dream who can impact the game at any number of positions. All the problems the Giants have endured covering tight ends? Here’s your eraser.

You have been reminded for years now that the Giants haven’t drafted a linebacker in the first round since Carl Banks in 1984, and miss the good old days when Big Blue was Linebacker U — remember the Crunch Bunch? Remember the Big Blue Wrecking Crew?

Simmons’ combine performance made jaws drop the way Saquon Barkley made jaws drop at the 2018 combine.

Dave Gettleman’s surgical free-agent strikes — middle linebacker Blake Martinez and outside linebacker Kyler Fackrell, and re-signing David Mayo — represent an upgrade in the unit over recent seasons, but none are game-changers like Simmons is for a defense devoid of game-changers.

Now, if I knew for certain that Simmons was the Next Lawrence Taylor, I would sign up for Simmons in a heartbeat. Of course, if the Bengals knew that, they might pass on Joe Burrow, and if the Redskins knew that, Ron Rivera would pass on Chase Young.

We have learned over the years, since LT retired following the 1993 season, that there is no Next Lawrence Taylor.

So this isn’t about Isaiah Simmons as much as it is about Daniel Jones. And to a lesser degree, Barkley.

Years of neglect building an offensive line did our beloved Eli Manning no favors when there was no escape from Father Time intercepting him.

New coach Joe Judge knows Tom Brady wasn’t any less of a statue than Manning was, and was an eyewitness to the way Bill Belichick built a Five Blocks of Granite wall in front of his GOAT quarterback more often than not.

It is incumbent upon Judge and Gettleman to build that wall for their young franchise quarterback.

They must draft one of the Core Four offensive tackles — Tristan Wirfs or Mekhi Becton or Andrew Thomas or Jedrick Wills — in the first round and the best available center in the second round with the 36th pick, if it isn’t a reach or if a pass rusher rated considerably higher is still on the board.

Jones can use his legs to escape the pocket, but that doesn’t mean anyone should expect him to start 210 straight games and be an Eli-esque Iron Man. The two games he missed as a rookie ought to serve as a reminder.

And if Barkley is ever going to silence the analytics crowd that rails against using a second-overall pick on a running back — even if he is a weapon more than just a running back — he will need something more akin to the kind of offensive line Ezekiel Elliott is privileged to have paving a path for him in Dallas, and Barkley needs it yesterday, because he will be entering his third season already.

And the analytics crowd already is holding up the example of Todd Gurley — cut by the Rams, signed to a one-year deal by the Falcons — as a cautionary tale for bestowing a second contract on a running back.

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Just three running backs currently fetch more than $10 million per year: Elliott ($15 million), Le’Veon Bell ($13.125 million) and David Johnson ($13 million). Free agent Melvin Gordon was forced to settle for $8 million from the Broncos.

Gettleman drafted Barkley to make Manning and Odell Beckham Jr. better, but failing to fix the offensive line sabotaged that plan.

The Jerry Reese Era ended badly, in no small part because of these decisions: Defensive tackle Jay Bromley over guards Gabe Jackson and Trai Turner in the third round of the 2014 draft. Left tackle Ereck Flowers with the ninth pick of the 2015 draft.

Cornerback Eli Apple over left tackle Laremy Tunsil (understood at the time because of the gas mask bong video on deadline) and tackle Taylor Decker in the first round, and safety Darian Thompson over guard Joe Thuney in the third round in 2016.

Tight end Evan Engram over right tackle Ryan Ramczyk in the first round of the 2017 draft. This is no slight against Engram, an enticing talent, simply an argument about positional value, and the fact Ramczyk has earned second-team and first-team All-Pro honors in 2018 and 2019, respectively.

That forced Gettleman to overpay free agent left tackle Nate Solder. And draft defensive end B.J. Hill over Pro Bowl tackle Orlando Brown Jr. in the third round in 2018.

There is no more room for error. Gettleman and Judge will have their pick of the litter: Wirfs, Becton, Thomas or Wills. Pick one of them, and give Jones the help he will need to be the Next Eli Manning. The help that the Only A Giant Eli Manning wished he had once his old Super Bowl gang was gone.