One by one, the longer- tenured members of the Mets veered toward a corner of the clubhouse, where the newly arrived September call-up soaked in his surroundings as if he were here for the very first time. He greeted each with the familiar smile he had flashed often during his meteoric rise.

Michael Conforto could do no wrong back then. Really, it wasn’t all that long ago, when his presence in this space had been a given.

From the day he began cashing paychecks for playing baseball, failure had been foreign.

Conforto’s polished lefthanded swing had taken him from Double-A to the major leagues, then to the World Series, and finally to Opening Night, when he started in leftfield for the defending champions of the National League.

“At the end of April,” he said, “I was on top of the world.”

Months later, the Mets phenom still isn’t sure when and where it all went wrong, but the general timeline is indisputable. After a fateful confrontation with Giants ace Madison Bumgarner, a massive slump followed, culminating in Conforto’s first demotion, and then a second.

advertisement | advertise on newsday

“You can’t take being here for granted. I think that played a part for sure,” he said this past week as he began his final chance to slap a bow on a miserable season. “I think I kind of took it for granted a little bit.”

‘A CRAZY GAME’

Oversimplification can interfere with understanding the fall. When it comes to Conforto, though, the temptation can be great, especially because his spiral is drawn in clear lines.

Consider the beginning of his descent, a day that began as a rite of passage.

Manager Terry Collins had protected Conforto from facing lefthanders, but a torrid April forced him to reconsider. The season’s opening month doubled as a warning shot to the rest of the league. Conforto, 23, posted a slash line of .365/.442/.676 with four homers and 18 RBIs. He ended April with an 1.118 OPS.

Mets videos

So when the Giants sent Bumgarner to the mound on May 1, Collins left Conforto in the starting lineup. The phenom relished the challenge. He had no reason to believe that he’d soon find a constant companion in failure.

“I probably would have thought you were crazy,” he said. “But that’s why this game is the way it is. It’s a crazy game. Anything can happen. It can humble you, bring you back down to Earth.”

Conforto faced Bumgarner three times that day. He lifted a fly ball and struck out twice, appearing overmatched at every turn. Nothing has been the same since.

“I really don’t trace it back to that,” Conforto said. “I think it’s a culmination of a lot of things. I wouldn’t pinpoint it just on that one start. Yeah, I think it was just a lot of different things.”

‘A LITTLE QUICK’

advertisement | advertise on newsday

On that long-ago Sunday afternoon against Bumgarner, Conforto stepped into the batter’s box as perhaps the most accomplished rookie in franchise history.

Through the first 77 games of his career, he hit .298 with 13 homers, 44 RBIs and a .924 OPS. To that point, no player in a Mets uniform had begun his career with a higher OPS — not Kevin Mitchell (.903), not Dave Magadan (.858), not David Wright (.856).

Conforto stood alone until he ran into Bumgarner. Even though he has a .164/.243/.318 slash line and a paltry .561 OPS in the big leagues since that day, he insists there is no firm connection linking his struggles to that one meeting.

“I really felt like I had some good at-bats,” Conforto said. “Obviously, I had three or four strikeouts [actually, three for the game], but I hit a ball really well to left-center. I think I stayed on some pitches, had some painted pitches that he got. I mean, he’s the best in the game.”

For Conforto, there was a far bigger culprit than Bumgarner. One rough game became two, and then two became four, and then four became eight. The downturn had begun. A stranger to struggle, Conforto soon learned how ill-equipped he had been to deal with it.

advertisement | advertise on newsday

“I think I was a little quick to really think something huge was wrong when I started to slide a little bit,” Conforto said, balling his fists and tensing his upper body to prove the point. “But again, that’s something you have to go through. It’s the first time I’ve struggled at this level. Not having gone through that, you kind of don’t know how to pull yourself out.”

‘THAT WAS TOUGH FOR ME’

On May 1, Conforto was humbled by Bumgarner. On June 1, he went 0-for-6 in a game in which he admitted going to the plate with “blind anger.” On July 1, freshly demoted to the minors, he woke up in Tacoma, Washington, for only his fifth career game in Triple-A.

With the lineup depleted and reeling from injuries, the Mets decided that they would be best served with Conforto in the minor leagues. He had hit bottom.

Demoted on June 25, he spent more than three weeks in the minors before rejoining the Mets. But after almost a month, he still hadn’t hit, and his playing time dried up. He was sent down again.

“When the team’s not playing well, that’s probably the hardest part, when you feel like you’re not helping the team, when you feel like you’re not part of the solution,” Conforto said. “Being a big part of the team coming into the year, being that starting leftfielder, and then moving away from that role, that was tough for me.”

Time has brought some clarity. Conforto can cite “a million things” that led to the most trying season of his career. He had badly wanted to help the team, perhaps too much, a common trap that led to pressing at the plate. It only compounded his inability to respond when the rest of the league adjusted.

“You know it’s coming,” he said. “You’ve played this sport before. But at this level, it’s quick, real quick. It could be mid-game.”

‘JUST A MINOR SETBACK’

Only three weeks had passed since he was last with the Mets. Still, as he moved into the clubhouse on Thursday along with the rest of the September call-ups, Conforto could barely hide his sense of relief.

He had spent his second demotion making a mockery of minor-league pitching, hitting .493 with six homers and 13 RBIs. Playing every day afforded him the luxury of rediscovering his disciplined plate approach. His swing again feels “natural.”

There is no time to fret about his place in the lineup, or to worry about making up for a lost season, or to dwell on the meaning of that long-ago confrontation with Bumgarner.

Conforto hopes to hit his way into more playing time, to help the Mets beat the odds, to relive last year’s playoff push, which he called “the most fun ride of my life.”

Mostly, he intends to take something lasting from his first taste of failure.

“I know I’m going to be here for a long time and have a long major-league career,” Conforto said. “I’ve always had that confidence. Just a minor setback. Obviously, I wish it didn’t happen. But it’s one of those things. It’s all part of the process. It will shape me into the player I’m going to be in the future.”