PORT ST. LUCIE, Fla. — If you didn’t know better, you might have thought Billy Eppler changed sides. Last September — just two months before joining the Mets for his second chance as a general manager — Eppler went to work for the William Morris Endeavor agency, his first outside job after two decades in major league front offices. In Eppler’s mind, though, the task was not much different than running a baseball operations department.

“Where I’ve found that I get the highest return on my efforts is when people grow,” he said on Thursday, in an interview at the Mets’ spring training complex here. “If someone feels better because of the contributions we’re making, I get a sense of purpose from that. And so all the jobs I’ve had since I’ve come into baseball have been that way.”

The idea at William Morris, Eppler said, was to help develop players and guide them toward their goals. His most shining example of this is Shohei Ohtani, the two-way sensation who chose the Los Angeles Angels in December 2017 largely because he trusted Eppler’s vision for his career.

The Angels fired Eppler in September 2020 after five losing seasons as their general manager, but last year Ohtani broke through as the winner of the American League’s Most Valuable Player Award. Ask Eppler about Ohtani, and he redirects his answer to another elite athlete.

“There’s a video I watch about Michael Phelps, on my iPad, and it’s like my own kind of mind-set video that just gets me in a good frame of mind,” he said. “And I watch it about Michael and his trainer and the work that they do, early in the morning, when he was accumulating gold medals like he was Pac-Man. And when you can play a role in that for a player — or for a young coach, a young scout, a young front office executive — man, that’s it. That’s where you feel good as a human.”

The anecdote is telling for what it reveals about Eppler’s inspiration and for what it omits: any actual mention of Ohtani. Eppler would rather not dwell on his tenure with the Angels, the good or the bad. He did touch on the tragic: the 2019 death of pitcher Tyler Skaggs, caused by the opioid fentanyl.

A jury in Texas last month found Eric Kay, a former communications director for the Angels, guilty of conspiracy to possess with intent to distribute a controlled substance and conspiracy to possess with intent to distribute a controlled substance resulting in death and serious bodily injury.

Several players testified that, like Skaggs, they had also received opioids from Kay. Since Skaggs’s death, Major League Baseball has implemented a testing and treatment program for players who abuse such drugs.

“There are safeguards in place per Major League Baseball,” Eppler said. “Very thankful for those. No industry or sport was immune to it. And now, thankfully, between the league and the union, there’s levers in place that can help in that.”

On the field, Eppler’s Angels teams were undone largely by poor starting pitching; no pitcher in his four full seasons qualified for the earned run average title with an E.R.A. under 4.00. That should not be a problem with the Mets if Jacob deGrom, Max Scherzer and Chris Bassitt are healthy atop the rotation.

Scherzer and Bassitt — the latter acquired for prospects in a trade from Oakland on March 12 — are two of only eight pitchers in the majors with 35 starts and an E.R.A. under 3.00 across the last two seasons. DeGrom was baseball’s best pitcher for three and a half seasons until elbow trouble cost him the second half of 2021.

“Look at that staff,” said Travis Jankowski, a speedy reserve outfielder who signed on Thursday, marveling at the names in his new clubhouse. “I’m an old-school guy — pitching and defense wins games, right? You look at our starters, and then you’ve got Francisco, you’ve got Robbie coming back, you’ve got Marte and Cahna, you’ve got all these guys. From top to bottom, it’s a pretty darn good roster and I think everyone can agree with that.”

Eppler inherited Francisco Lindor and Robinson Cano, but added outfielders Starling Marte and Mark Canha and infielder Eduardo Escobar in free agency, giving the Mets depth in everyday-caliber players. They also have infielders Pete Alonso, Jeff McNeil and J.D. Davis, and outfielders Brandon Nimmo and Dom Smith.

“It takes a lot of pressure off each individual guy,” Nimmo said. “Let’s take it from a scientific standpoint: We’re going West Coast, East Coast, night games, day games — there’s a good chance you break down at some point. Guys understand it’s better to have a day off now and then than it is to go all-out and be gone for two weeks. The game has changed a little bit in that way.”

Eppler, a San Diego native who pitched at the University of Connecticut, was raised on traditional scouting principles with the Yankees, where he rose to become Brian Cashman’s top lieutenant. At 46, Eppler retains a curiosity about new ideas — “I value people’s ability to rethink things,” he said — and Nimmo said players have noticed.

“He’s trying to bring a lot of different ways of thinking to the clubhouse and to the staff,” Nimmo said. “So if one guy is thinking one way, he wants to balance that out by bringing in someone that thinks a complete other way. He’s big on that, making sure there’s a lot of different kinds of input and hopefully one of those clicks.”

From his years with the Yankees, Eppler knows one group is eager to give its input: New York fans. He said he has never forgotten his first game at Shea Stadium, in the scout seats behind the plate in 2005, surrounded by a kind of intensity distinct to Queens.

Mets fans demand winning but retain an underdog’s edge — even with owner Steven A. Cohen’s billions — in a city they share with the Yankees. Eppler, who has settled in Long Island, said he is here to serve.

“What do they want? They want to win, and they want to win a lot,” Eppler said. “Winning one year is great — but winning over a long period of time — wow, that is, like, . You can really fill the belly if you do that. So I try to approach the job like a duty and obligation to the fan. And I’m happy to be able to fight for this group.”