Michael Conforto #30 of the New York Mets celebrates his...

Michael Conforto #30 of the New York Mets celebrates his third inning home run against the Oakland Athletics at Citi Field on Sunday, July 23, 2017 in the Queens Borough of New York City. Credit: Jim McIsaac

Nothing can measure the long distance from spring training to the trading deadline better than this: Back in March, the Mets looked set and Michael Conforto was such a question mark that he seemed like a candidate for the minor leagues. And now, the team is in intense flux and Conforto is their greatest constant. He also happens to be their best player.

Funny, how fickle forecasts and scouting reports can be. Sad, to think where the Mets might be if circumstance had not forced their hand.

Maybe he would not have begun the season with the Mets if Juan Lagares didn’t suffer an oblique strain in March. Maybe Conforto would not have cracked the lineup if Lucas Duda was not injured in late April, causing Terry Collins to temporarily move Jay Bruce to first base, opening an outfield spot. Maybe the Mets would be in even more disarray.

As it is, Conforto was their only All-Star and played in the game despite having been on the disabled list with a bruised hand. He emerged from it on a tear, having hit .350 with three doubles, five home runs and 11 runs batted in since the break — fueling the team’s mild resurgence (6-4).

The resurgence probably has been too mild, though. As Terry Collins said Sunday after the 3-2 loss to the Athletics, an 8-2 homestand would have qualified as “good enough.” So, the team likely will jettison whoever it can before the July 31 deadline. It is getting clarity about which players are keepers. Conforto, 24, is at the top of that list.

He is “destined” to be a premier player, Collins said the other day, adding, “He knows he’s going to hit. He works hard and [he knows] not to change his swing, like what happened last year. He’s trying to stay consistent.”

That includes attitude and outlook. No gushing over his .294 batting average and career high 19 home runs. No handstands over having been the lone bright spot Sunday (2-for-4, including a home run) or having hit five homers in his past 10 games.

“Over the course of a season, there are going to be high times, low times. I think it has just been trying to stay relaxed and get back to doing what I do. I don’t think I’ve really changed much. I think it’s just staying comfortable up there,” Conforto said.

He deserves points for maintaining his stroke while learning a new and tough position, centerfield (and continuing to erase a bogus reputation as a weak defender). “Whenever you’re trying to improve in every aspect of the game, you’re making yourself an overall better player,” he said. “I think it helps me stay out there. The fact that I can play all three positions, I think it helps me stay in the lineup.”

His future probably is at one of the corner outfield spots, which is an issue for another day. Right now, the Mets are trying to get through this week, sorting out who will be here and who won’t. Right now, it is both good news and bad that nine of his home runs have either given the Mets a lead or tied a game. Good, because it shows a clutch streak, bad because it reveals the Mets have been behind or tied too much.

A huge reason for that is that they simply have not gotten enough out of Yoenis Cespedes, the presumptive franchise cornerstone who has not hit a home run in a month (June 23). “We’ve just got to get the big guy going,” Collins said. “When we get him going, it’s a whole different lineup.”

Truth is, however, right now and possibly for years to come, Conforto is the Mets’ big guy.