Unlike last year, don’t expect big reinforcements

WASHINGTON — The 2015 Mets through 77 games: 40-37 record, 276 runs scored (14th most in the National League).

The 2016 Mets through 77 games: 40-37 record, 276 runs scored (14th most in the NL). Deja phew! The difference this time? Yoenis Cespedes already is here, and it’s hard to envision an equivalent arriving by the Aug. 1 non-waivers trade deadline. The bulk of this rescue mission must be performed by those already on site.

The defending NL champions suffered their fourth consecutive loss Wednesday night at Nationals Park, 4-2 to Max Scherzer and three relievers, completing a three-game sweep for Dusty Baker’s reborn group as Mets refugee Daniel Murphy slugged two homers. Now six games out of first place in the National League East, at least the Mets can return home to Citi Field … where the Cubs, baseball’s best team, await them on Thursday night. (Scratch that “at least.”) “We’re just not even giving ourselves chances,” Terry Collins said afterward. “… We can’t give our pitchers any room to work.”

The Mets broke a 14-inning scoreless skid with James Loney’s two-run homer in the ninth off former Yankee Shawn Kelley and brought the tying run to the plate in the form of rookie Brandon Nimmo … who struck out looking to end the game. In the eighth, outfielder Alejandro De Aza whiffed with teammates on second and third and the Mets trailing by two. De Aza, with a putrid .158/.208/.232 slash line, can’t stick around much longer. He is the Mets’ 2016 equivalent of John Mayberry Jr.

For the most part, though, this Mets lineup and roster shouldn’t require the sort of mass infusion their immediate predecessors received last July. Sure, Jose Reyes will be up soon enough and could help, but he no longer is a highwattage player. While Michael Conforto could benefit from his demotion to Triple-A Las Vegas and return refreshed, he’d just be giving the Mets what they planned on receiving from him in the first place. Lucas Duda’s re- turn from the disabled list will provide a boost, though Loney has performed admirably in his stead.

Yulieski Gourriel? If the Mets actually sign him, a long shot, the Cuban free agent would require about a month to get ready for his big-league debut. A trade for a third baseman or outfielder? Possibilities, yet the Mets’ prospect arsenal was depleted by last year’s spree for Cespedes, Tyler Clippard, Kelly Johnson and Juan Uribe, limiting their ability to pull off a high-impact purchase. What’s most confounding about this Mets team is that, while their overall offensive numbers stink, the only position that has performed significantly below league average is catcher, where Travis d’Arnaud just returned to action last week after a long stint on the disabled list. A large quantity of their struggles at the plate can be attributed to their leagueworst (by far) .205/.286/.321 slash line with runners in scoring position.

“They’re major-league players, so they’ve got to understand, if they keeping adding pressure on themselves, they’re going to continue to struggle,” Collins said. “It’s one of the things we make sure they try to understand. They’ve got to be themselves. If you try to be something you’re not, if you try to go up there or hit the ball out, try to do whatever you’re not doing, you’re not capable of doing, you’re going to struggle. We’ve just got to continue to try to get up and get a good pitch to hit and try to barrel the ball up and take what happens.”

To avoid leaning on another August-September burst, the 2016 Mets must defy the narrative established by the 2015 bunch and start hitting better in July. With these guys, mostly.

“Everybody’s doing what you’d kind of expect. Travis just got back,” Collins said before Wednesday’s game. “It sounds real trite, but we’ve got to grind this out. We’ve got to get through this tough time.”

If they don’t, then the players themselves will deserve a healthy share of the blame. They can’t expect a cavalry of outsiders to bail them out this time.