The Mets are on another steep slide.

Dropping their fourth straight game in the first of a doubleheader at Citi Field on Wednesday, the Mets got smoked 10-3 by the Cubs ahead of Francisco Lindor’s long-awaited return to the lineup from a calf injury that night.

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It was as if the rowdiest fans in attendance — a horde of Norwegians in town for the World Cup — could feel the organization’s glimmer of hope. Taking over the section just below the jumbotron, a sea of red soccer jerseys showed their support with coordinated chants and dances throughout the stands.

Even they quieted by the time the Cubs doubled the Mets’ score.

Since this latest losing streak began, the Mets have been outscored 40-14. Their closest loss was Tuesday’s 9-6 defeat.

“It’s tough, I’m not going to lie, obviously there’s frustrations for all of us in here,” Mets manager Carlos Mendoza said. “We got another one coming up pretty soon. The last thing we want is to sit here and start feeling sorry for ourselves. Like, you have to punch back.

“You got to find a way to punch back and keep going. You got to get back up, but it’s not easy right now.”

While Lindor should give the Mets a boost, there is still uncertainty surrounding Juan Soto, who was held out of both games with tightness in the left side of his back.

Mendoza wouldn’t rule out a stint on the injured list for Soto, who was receiving treatment and still being evaluated Wednesday.

Lindor and Soto have appeared in only nine games together this season.

“It is what it is, right?” Mendoza said of potentially losing Soto as Lindor returns. “Hopefully, we get those two in the lineup for a long time here for the rest of the season and we can make a run at it.”

The Mets, who were without Lindor for a 53rd consecutive game, blew a 3-0 lead in what became a noncompetitive first game Wednesday.

By way of a couple of home runs, the Mets opened the scoring in the third inning.

Bo Bichette ripped one to left field for a base hit before Jared Young blasted his sixth homer of the season. The very next batter, Francisco Alvarez, then unloaded a 437-foot shot into the center field stands for the 3-0 lead.

It was a short-lived lead as the Cubs easily caught up the following inning thanks to an RBI double from former Met Michael Conforto and a two-out, two-run homer from Michael Busch.

Cubs starting pitcher Javier Assad made quick work of the bottom of the fifth, retiring Carson Benge, A.J. Ewing and Bichette.

The same couldn’t be said for Nolan McLean, who had a mixed bag of a day on the mound.

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After Nico Hoerner popped one into deep right field for a double, Miguel Amaya had a base hit that put runners on first and third. McLean hung a 95.5 mph four-seam fastball over the plate for Dansby Swanson to launch into the short porch in center for a 6-3 lead.

McLean was replaced by Jonathan Pintaro before they took the field in the sixth inning, wrapping up his day with seven hits, six runs, two walks, nine strikeouts, two home runs and two hit batters.

It was an even rougher outing for Pintaro, who loaded the bases in the eighth after opening the inning with back-to-back walks and hitting Amaya with a pitch.

Swanson then hit a grand slam to take a commanding 10-3 lead, giving him a 2-for-4 showing from the plate with seven RBIs.

“The season is definitely testing our mental fortitude, for sure,” McLean said. “Each day, we’re all having conversations with each other figuring out how we can get better. Trying to see what each other’s doing that we might not be noticing with ourselves, just getting a different perspective on things.”