Jacob deGrom received his big contract before this season, ensuring he will be the cornerstone of this Mets rotation deep into his 30s. It was a smart move by the organization and player to continue a marriage that had blossomed.

Study the Mets roster for the next player worthy of such a deal that would lock him up through his prime years and you stop at Michael Conforto, still only 26 years old and already one season into arbitration.

Team officials have used the term “core player” when discussing Conforto with me. It explains why the Mets wouldn’t put Conforto in a deal for J.T. Realmuto last winter and didn’t give thought to trading the outfielder heading into July 31, when their season appeared lost.

Conforto has rebounded from a sluggish first half by his standards. His 29 homers are a career high and he owns an .847 OPS for the season. In an outfield with multiple movable pieces, Conforto is the rock. And players of his ilk certainly don’t grow in the parking lot at Citi Field, especially when you consider the top 15 prospects or so in a depleted Mets farm system are all infielders and pitchers.

Maybe the Mets had a better version of Conforto in Jarred Kelenic, but that player isn’t returning, after general manager Brodie Van Wagenen traded the stud prospect to the Mariners last offseason as the headliner in the deal that netted Edwin Diaz and Robinson Cano. It’s a trade that looks worse for the Mets with each passing day.

Jeff McNeil, J.D. Davis and Dominic Smith have all played outfield this season, but who knows how many will remain there and who among that group might be traded (though McNeil is virtually a lock to return). Another outfielder, Brandon Nimmo, had a chance this season to prove he was an everyday player but spent much of the year on the injured list.

Conforto, who is earning $4.03 million this season, can hit free agency after 2021, meaning it’s not too early to consider a deal that would keep him with the Mets long term, buying out his two remaining arbitration years.

“I think that is always on players’ minds, they want to have that security and I know I am going to be under their control for the next two years so it’s kind of something that during the season, it’s not something I really want to talk about,” Conforto said Tuesday. “When we get into the offseason and kind of leading up to spring training, I guess those conversations will be had, but I love it here and I would love to continue to play here.”

Conforto still hasn’t returned to the All-Star form he displayed in 2017, a season that ended with him undergoing shoulder surgery. But there is something to be said for a player who produces a 125 OPS+ (meaning he is 25 percent better offensively than the average player, adjusted for league and ballpark) and can be counted upon to play every day.

“I feel I have been a core guy in this lineup, in this organization,” Conforto said. “I feel like aside from the surgery I have been pretty durable — a guy they can count on to go out there every single day to go out there and play through some soreness and small things here and there. I take pride in that. To be durable is very valuable.”

The Mets eventually will have to pay Pete Alonso, but probably want to see him play another season or two before outlaying the big dollars. There is no hurry, as he won’t even be arbitration eligible until after the 2021 season.

Of course, if the Mets want Conforto locked up, that will mean negotiating with Scott Boras, who usually pushes his clients to free agency. But Boras works for Conforto, not the other way around.

“Where else would you want to play other than New York?” Conforto said. “I leave that to Scott and Brodie to work that out. All I can do is play as well as I can. I feel like I haven’t put a full season together where I can really say that I have reached my full potential to this point.”

From the vantage point of Fred Wilpon’s checkbook it might be wiser to lock up Conforto before he reaches his full potential than after.

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