New York Mets starting pitcher Noah Syndergaard looks on from...

New York Mets starting pitcher Noah Syndergaard looks on from the dugout in the ninth inning of the National League wild-card Game against San Francisco on Wednesday, Oct. 5, 2016, at Citi Field. Credit: Newsday / Thomas A. Ferrara

For years, the Mets watched with envy as members of their own division maintained a firm grip on an elusive ideal.

The Braves once defined sustained success, while everyone else endured a more typical boom-and-bust cycle. That included the Mets, whose busts have lasted longer than their booms.

In 55 seasons, the Mets have made the postseason in consecutive seasons only twice. That includes this season’s second-half surge to claim one of the National League’s wild cards a year after reaching the World Series.

“It feels like yesterday we were talking about this last year,” captain David Wright said earlier this week, when he implored the team’s younger players to savor a rare moment. “And now to be back two years in a row, this doesn’t happen very often, and it certainly hasn’t happened very often here.”

The Mets never have reached the postseason in three straight years. But after Wednesday night’s 3-0 loss to the Giants in the wild-card game — a defeat that ended a season of high expectations — the Mets came away with reason to believe that their success may finally be sustained.

Though the Mets were disappointed that they were denied by Giants ace Madison Bumgarner, their clubhouse was filled with hugs, handshakes and thoughts of returning next October.

“I feel like it was a good season because of all the adversity we had to go through,” said Jose Reyes, whose return jumpstarted the Mets. “We had injuries and stuff. That doesn’t mean it’s an excuse. But we were able to make it to the playoff, a one-game playoff. Like I said, we feel very good about this group. Hopefully, I’ll be here next year, because next year is going to be even better.”

Reyes almost certainly will be back with the Mets, who hold a team option for the league minimum. But other questions abound, including whether the Mets can retain Yoenis Cespedes.

The slugger is expected to opt out of his contract and become a free agent after hitting .280 with 31 homers and 86 RBIs. But compared to this time a year ago, when Cespedes also was eligible to become a free agent, there is a deeper belief within some in the organization that he will be back.

Regardless of Cespedes’ fate, the Mets will return their vaunted collection of young arms, a group that remains the foundation of the team. Matt Harvey, Jacob deGrom and Steven Matz are coming off surgery, but all are expected to be healthy by spring training. Zack Wheeler also is expected to benefit from an offseason of rest after he hit bumps in his rehab from Tommy John surgery.

But those injuries helped the Mets discover an extra layer of insurance in rookie righthanders Robert Gsellman and Seth Lugo, whose second-half performances helped to salvage the season.

“Surprisingly, our greatest strength was deeper than we even expected that strength to have been,” general manager Sandy Alderson said this week. “So while we did lose the top end of that strength, fortunately we had something in reserve.”

That depth also spared the Mets at second base. When Neil Walker went down with a back injury and Wilmer Flores never returned from a wrist problem that required surgery, rookie T.J. Rivera filled the void.

“We have a plethora of talent here, we really do,” rightfielder Jay Bruce said. “With the pitching that came up that really did an awesome job and the pitching that we already have that’s awesome that’s going to be healthy, there’s going to be some pretty amazing depth there.”

Next season, that experience should benefit the Mets.

“That was good to see, all the young players come up from the minor leagues and contribute in this kind of situation,” Reyes said. “That’s what you want from the organization.”

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