The Mets’ Francisco Alvarez reacts on second base after his...

The Mets’ Francisco Alvarez reacts on second base after his two-run double against the Philadelphia Phillies during the seventh inning of an MLB game at Citi Field on Saturday. Credit: Kathleen Malone-Van Dyke

For four seconds that felt like forever Saturday evening, as Francisco Alvarez’s game-swaying hit floated toward left-centerfield, he ran hard but focused mostly on watching — along with the rest of the Mets and their largest Queens crowd of the season.

Phillies reliever Orion Kerkering had thrown Alvarez a sweeping slider down and away during the Mets’ rally in the seventh inning. Somehow Alvarez yanked it. He didn’t hit the ball particularly hard or particularly far, but it landed in just the right spot. Weston Wilson, coming from the left, dived out of desperation; he had no real shot. Johan Rojas, coming from the right, fielded it on a hop.

Alvarez reached second base with a two-run double, turned to the Mets’ dugout and went full starfish: legs spread, arms up, head held high. The Mets had broken through, finally, producing plenty to pick up a 6-3 win over the Phillies, and so too has Alvarez.

After a 2-for-4 effort against Philadelphia, Alvarez is batting .286 with a .786 slugging percentage in the past week and a half. Six of his eight hits have gone for extra bases.

“He’s locked in right now,” manager Carlos Mendoza said. “There’s rhythm, there’s conviction. He’s not missing much.”

After collecting only six home runs in his first 85 games, Alvarez has five in his past nine. The latest came against Phillies lefthander Ranger Suarez in the second inning, a laser to left.

What might look like an overnight change actually is the result of Alvarez’s months of work with hitting coaches Jeremy Barnes and Eric Chavez. The primary problem: His freakishly fast hips were too fast, opening too early, which threw his swing out of whack. Even for a player as strong as Alvarez, it’s hard to hit the ball far — or at all — when one’s body isn’t moving cohesively.

 

Now that that he has figured it out, Alvarez’s power is back, creating a different dynamic in the bottom half — usually the bottom third — of the lineup for the Mets (86-69).

“It ended up being the difference today. If we don’t get that production from him, it’s a tie ballgame, obviously a different circumstance,” said Brandon Nimmo, whose go-ahead single in the seventh preceded Alvarez’s double. “Getting that kind of production from the bottom of your lineup is invaluable. It’s a separator. And we’ve been able to get a lot of that throughout the year. It’s been incredible. It lengthens your lineup and just makes it that much tougher to get through.

“They’ve had unbelievable at-bats — a lot of people down at the bottom, but Alvarez especially lately. He loves the big moments. I love that about him. He doesn’t shy away from them. He rises to the occasion and he loves this atmosphere too.”

What does Nimmo see from Alvarez in those spots that tells him that?

“He’s almost foaming at the mouth to get up there,” Nimmo said. “The way that he walks around the batter’s box, the mannerisms, the body language when he’s up there. He takes a swing and steps back out. It just tells me he wants that moment and he wants to take it head on.”

Alvarez said: “I take what the game gives me. If the game gives me that, I really love that. If the game doesn’t give me that, I believe in all my teammates.”

Alvarez was the highlight in what was in effect a dry run for potential playoff games at Citi Field.

Sean Manaea, their Game 1 postseason starter if they get there, pitched another seven innings (three runs). Pete Alonso reached base five times. Jose Iglesias had two more hits, including a double. Luisangel Acuna continued his inexplicable show of power with his third home run in a week. Edwin Diaz recorded the final four outs for the save.

Altogether, they prevented an NL East title clinch for the Phillies (92-63) for at least another day. The Mets also remained two games ahead of Atlanta for the final NL wild-card spot.

And they did all that in front of an announced 44,152, the fifth-largest regular-season crowd in Citi Field history.

“I alluded to it beforehand that we were going to have playoff baseball here, and that’s what it felt like this afternoon,” Nimmo said. “It was high-energy. Every pitch mattered.”

Mendoza said: “That’s what it should look, it should feel like, especially when we’re playing meaningful games in September. It’s what you signed up for. It’s what you dream [of], prepare for. But again, we gotta continue.”