Greg Carvel had a challenge for Zac Jones when the pair spoke at their end-of-season meeting in 2020.

Jones scored only three goals his freshman season, and Carvel knew the UMass defenseman — already a Rangers draft pick — was capable of more.

So they crafted a plan where Jones shot around 200 pucks daily in his driveway.

He sent Carvel clips to check in.

And a year later, in the first period of the Frozen Four against Minnesota Duluth, Carvel designed a play that required puck movement and an eventual shot by Jones.

The reaction, when the puck snapped off Jones’ stick and zipped through a tight window underneath the crossbar, was “priceless,” Carvel said.

Jones had refined another strength, and that goal highlighted a stretch in the NCAA Tournament — which ended with a national championship — that changed everything.

When he started college, Jones needed to add physicality to shake the negative connotation that came with being an undersized defenseman.

He also made strides with fine-tuning his shot and skating UMass, adding to the shiftiness and puck possession that has defined his reputation with AHL Hartford (31 regular-season points in 2022-23) and the Rangers.

And after signing a two-year extension Friday, Jones earned his next chance to earn a full-time NHL spot.

The Rangers think he’s mastered the AHL and can stick with the Blueshirts this time, according to The Post’s Mollie Walker.

“They can’t change how tall they are,” former UMass assistant Ben Barr, and now Maine’s head coach, told The Post about the 5-foot-10 Jones. “None of us can. But they can change, they can always add a dimension to their game. … [Jones] found a way to balance the fact that he wasn’t gonna be 6-foot-3, and I’m sure he’s continued to do that the last two years.”

For Barr, the key to an NHL break — whether it’s Jones’ or anyone else’s — boils down to maximizing a window of opportunity.

Barr has observed plenty of former players with the Minutemen and at Providence College succeed at that.

Cale Makar with the Avalanche; Mario Ferraro with the Sharks; Brandon Tanev, now with the Kraken, with the Jets: All, at one point, got a call-up or earned late-season ice time after an entry-level deal, and they started “running with it.”

And then there’s Jones.

The 22-year-old and third-round pick in 2019 logged stretches of NHL games — 10 his rookie year, 12 in 2021-22, 16 last season — but that hasn’t translated to a permanent, top-six role.

“There’s so many good hockey players when you get filtered down to the best league in the world, and he was drafted by a team that obviously had a good D corp, a young D corp,” Barr said. “So maybe that opportunity wasn’t as good as it might’ve been in other NHL teams at the time, and you know what? That’s life, and he’s a kid that just doesn’t complain.”

When Carvel recruited Jones, concerns emerged about checking.

Jones neutralized that disadvantage as a freshman, compiling 23 points in 32 games, and his encore featured 24 points and a national title.

Jones enhanced details that size “often covers,” Carvel said.

Carvel and former UMass assistant Jared DeMichiel — now Michigan State’s associate head coach — said Jones didn’t plan to ink his deal entering the 2021 NCAA Tournament.

Jones prepared to sign an off-campus lease with teammates, Carvel said.

In the postseason, though, Jones starred while breaking out pucks and sparking the Minutemen’s power play.

Jones’ inner circle, and the Rangers, knew he was ready.

“He’s not a guy that’s ever gonna crush people,” Carvel told The Post, “but you have to, at some point in hockey, be able to be physically involved in defending.”

The Rangers already have a 5-11 defenseman with Adam Fox, and Carvel said typically “you can’t have two or three guys” with Jones’ build.

But in the offseason, Jones has changed workout plans to focus on power, DiMichiel said.

The defenseman now has a taste of the NHL.

He has the scenario for a fresh start, too.

At some point, though, Jones will have to prevent a window with the Rangers from slamming shut.

They don’t “stay open forever,” Barr said.

“I think [Jones] knows about that potential opportunity,” DeMichiel said. “From talking to him, I know he’s switching his training up, who he’s training with, what he’s doing for skills. … It seems like this is a potential make-or-break opportunity, and you want to make it and I think you gotta do that kind of stuff. He’s got a good mindset for it.”