NEW YORK -- Jeff McNeil and Michael Conforto are back in the Mets’ everyday lineup, Brandon Nimmo and J.D. Davis are set to join soon, and still New York’s offense has not managed to ramp up its production. In what’s becoming a troubling trend, the Mets couldn’t score against former teammate Zack Wheeler in a 4-2 loss to the Phillies on Sunday at Citi Field, settling instead for a series split.

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The Mets have lost eight of their last 13 games, which has been palatable only because their NL East lead has barely budged, slimming from five games to four. Over that stretch, their hitters have averaged 2.2 runs per game and been shut out four times.

Even for a first-place team, such offensive figures are hard to ignore. Eight weeks after their firing of hitting coach Chili Davis, the Mets have posted nearly identical statistics under his replacement, Hugh Quattlebaum. Some of that has been due to the fact that they’ve played long stretches without multiple key offensive pieces. But the rest has been because nearly every member of the starting lineup has underperformed compared to previous career norms.

To a man, the Mets insist that will change in time.

“I don’t think there’s any panic or rush or anxiousness at all,” said first baseman Pete Alonso, who had three of the Mets’ seven hits. “We’re still not even halfway over with the season. We still have so much baseball left. … There’s going to be times when we’re scorching hot, and there’s going to be times where it’s not going to be like that.”

The Mets had two prime chances to score against Wheeler on Sunday. The first of them occurred in the first inning, when Francisco Lindor doubled and Alonso singled with one out. But Conforto popped up, and James McCann grounded out to end that threat. Four innings later, the Mets put their first two men on base. After Luis Guillorme lined out, manager Luis Rojas elected not to use a pinch-hitter for reliever Corey Oswalt, who bunted. McNeil then flew out to end the inning.

They finally pushed across two runs against the Phillies’ bullpen to avoid a shutout, on an Alonso RBI single and a Kevin Pillar homer.

“I think it’s something that’s going to click,” Rojas said of the offense. “The guys are going to connect at-bats. We have Conforto’s presence. We have McNeil’s presence in the lineup. Those guys are going to start hitting, and they’re going to start connecting with Lindor and Alonso, who are swinging better right now.

“It’s something that I expect to happen, because we’ve seen it happen in the past.”

It was telling that, when Major League Baseball announced position player finalists for the All-Star Game on Sunday, no Mets were among them. What’s more, every Met was several hundred thousand votes or more away from qualifying, which is unusual considering the pedigree of this bunch. McNeil, Lindor, Alonso, Conforto and McCann have all been All-Stars in the past. Producing at that level is not foreign to them.

“We just collectively have not gotten hot at the same time,” Pillar said earlier this weekend. “We’ve had an offensive explosion here and there, but just consistently throughout a game, it seems like [when] we get big hits from someone, we have at-bats that aren’t so good from someone else. It just seems like we haven’t gotten on a roll yet. But we are confident in each other.”

Unlike the rotation, which the Mets figure to upgrade before the non-waiver Trade Deadline, the lineup is not so easy to fix. The Mets have veterans entrenched at every position. The team is not going to replace slumping catcher McCann, for instance, after signing him to a $40.6 million deal this winter. They are certainly not going to trot anyone other than Lindor out at shortstop for the rest of this season. While it’s possible the Mets could deal one of their other players in a blockbuster-type deal, it’s never easy to blow up a contending roster midseason.

And that’s what makes the Mets’ current offensive predicament so difficult to solve. The team has little choice but to keep trotting out the same eight hitters and hope that water rises to its level. To that end, when Davis returns from the IL in early July, the Mets should be able to put their Opening Day lineup on the field for the first time since early May.

Perhaps that will be enough to spark Lindor, McNeil, Conforto and others. Perhaps it won’t.

It’s not as if the Mets have much other choice but to wait and see.

“People forget how long 162 games really is,” Alonso said. “I mean, it is a marathon. I have no doubt that we’re going to be scorching hot. It’s not necessarily about how you start. It’s about how you finish.”

Worth noting
The Mets announced after Sunday’s game that Marcus Stroman would depart the club for a few days following the passing of his grandmother. Regardless of whether Stroman goes on MLB’s bereavement list, the Mets expect him back in time for his next start against the Yankees.