Brett Baty #22 of the Mets celebrates his sixth inning home...

Brett Baty #22 of the Mets celebrates his sixth inning home run against the Cleveland Guardians with teammate Mark Vientos #27 at Citi Field on Friday, May 19, 2023. Credit: Jim McIsaac

In the 18 months since Steve Cohen hired Billy Eppler, the general manager’s overarching vision — funded by the multibillionaire owner — has been clear: Develop a perennial contender on the strength of homegrown studs while filling in the gaps with other players as needed. It’s a foundation-laying process that Eppler has said can take a half-decade or longer.

The key is being adamant about not parting with top prospects. In the offseasons, that strategy has meant spending big — spending historically huge — on free agents instead of making trades. Last summer, it meant something less than an all-in approach to Eppler’s first trade deadline as the Mets moved through one of the greatest regular seasons in franchise history. They retained all 19 of their top minor-leaguers, Eppler very specifically noted at the time, in the hopes of a bountiful tomorrow.

That prospect patience is beginning to pay off. Francisco Alvarez, Brett Baty and Mark Vientos have become “the Baby Mets,” as Francisco Lindor calls them, and are contributing in major ways. Less than one-third of the way through the season, the rookie trio represented one-third of the lineup Friday night.

“Hitting is contagious, and they’re having quality at-bats. They’re working pitchers, they’re getting good pitches to hit and they’re driving them,” said Lindor, whose walk-off single Friday night in the 10th inning gave the Mets a 10-9 win over the Guardians. “I got to first base, I opened my arms and the first person is Baty running to me. We all celebrated together, and that’s what it’s all about. I don’t care whether you’re 41 years old or you’re 21 years old. We all celebrate together when we win, and when we have bad days, we’re going to stay together. That’s what good teams do.”

Alvarez, Baty and Vientos joined the organization in consecutive years — Vientos in the second round of the draft in 2017, Alvarez as an international free agent in 2018 and Baty in the first round of the draft in 2019 — and largely climbed the minor-league ladder together. They drew plenty of trade interest from other clubs, but the Mets, across ownerships and front-office regimes, resisted.

For Eppler’s Mets, having all three with the big-league team this soon was not the plan. But stuff happens. Omar Narvaez got hurt, so Alvarez got the call. Eduardo Escobar stunk, so Baty got a shot. Vientos mashed for Triple-A Syracuse — for a second season in a row — so the bosses relented and called him up Wednesday.

In two games, Vientos has three RBIs (and was on the bench for a game, for some reason). Alvarez has hit five home runs in 27 games, approaching the total (eight) hit by Mets catchers all of last season. And Baty quickly earned his way into the No. 5 spot in the batting order, serving as Pete Alonso’s protection. He is hitting .250 with an above-average .758 OPS.

“These guys are like my brothers,” Alvarez said through an interpreter Friday. “They’re my family. We’ve been playing together for a long time and having them around, it brings me a lot of joy. I hope I can be around them for the rest of my career.”

After a slow start in which he was the de facto backup catcher to Tomas Nido, Alvarez has had a strong May, slashing .261/.346/.609. He came through with the tying hit when the Mets were down to their last out in each of his past two games. The only other player to do that in the past decade, according to Stats Perform, was Albert Pujols in 2017.

In spots in which Alvarez clearly was overswinging and trying too hard late last season and early this season, he now is excelling.

“My confidence has really gone to another level,” he said. “I feel like the game has slowed down a little more too as well.”

They’re enjoying themselves, too.

“I have a friend who always says the team that wins is the team that has fun,” Alvarez said. “So hopefully we can continue having a little bit more fun.”

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