Mets leave no doubt in NLCS Game 5 victory, plant good vibes as they head to L.A.

The Mets showed up at Citi Field for Friday’s NLCS Game 5 desperate to keep their remarkable October alive. Staring into the playoff abyss, down three games to one to the Dodgers, the theme going in was survival. Or, as these Mets refer to it, business as usual.

What other team would think to roll out the Temptations to perform “My Girl” — Francisco Lindor’s walk-up song — knowing that it could happen on the brink of elimination? But here’s the thing: When red alert is your default position and do-or-die situations become second nature, there’s obviously nothing that can faze these Mets.

And that now includes their current mission: Flying another 3,000 miles to win two games at Chavez Ravine and punch their ticket to the World Series, a trip willed into existence by Friday’s 12-6 rout of the Dodgers before a giddy sellout crowd of 43,841.

“It’s definitely possible,” said Brandon Nimmo, who contributed an RBI single despite being hobbled lately by plantar fasciitis. “I think if any team can do it, we can. We’ve played with our backs against the wall all year and we’ve been able to rise to the occasion. Some might even say we’re at our best at that time.”

Nimmo, the most insightful Met, knows what he’s talking about. As for stepping up in big spots, the list was extensive for Game 5, and the Mets are confident that will continue for Games 6 and 7 at Dodger Stadium.

Edwin Diaz, who dominated in his six-out appearance, echoed the clubhouse-wide belief that they can close the deal out in L.A. “We’re a really good team and we trust ourselves,” he said. “We’ve come from a lot of adversity and I think we can beat them.”

Why not? After Pete Alonso landed the first punch Friday, the Dodgers caved. The pending free agent, who is determined to call Citi Field home for as long as possible, keeps making sure they keep the lights on for him this month.

With two on in the first inning, the Dodgers’ Jack Flaherty threw an 85-mph slider to Alonso that he probably thought was in a safe space, only a foot above the plate. But Alonso reached down and somehow golfed a 432-foot homer into the blacked-out batter’s eye in centerfield (a member of the orange-clad 7 Line Army actually stretched for a nifty one-handed grab). Staked to that 3-0 lead, the Mets tacked on plenty from there, but it was fitting that it was Alonso who delivered the party-starter.

Asked later how he could hit a pitch that low that far, Alonso shrugged.

“Over a million swings lifetime,” he said. “Honestly, it’s inexplainable. It’s the magic of the postseason. And I’m just happy I squared it up.”

With the Mets facing elimination, just like that Game 3 night in Milwaukee, Alonso came up big when it mattered most. And he spurred his teammates, too, as they piled on. The Mets smacked 14 hits, incredibly didn’t strike out once — shocking in this era — and ripped Flaherty for eight runs in only three innings after he dominated them in Game 1.

Starling Marte went 4-for-5 with three doubles and three RBIs, becoming only the sixth Met with a four-hit game in the playoffs and first since 2015 hero Daniel Murphy, also in Game 4 of the NLCS. Jesse Winker was the first Met to have two triples in the same postseason. Perhaps most surprisingly, Francisco Alvarez, once slumping but now impossible to get out, went 3-for-4 with an RBI single that helped fuel the Mets’ five-run third inning that blew things open. Talk about your playoff magic.

“We’re capable of putting together games like this, especially when one through nine are clicking, not chasing,” manager Carlos Mendoza said. “We showed up today. We needed that.”

Friday’s vibe brought flashbacks of the Mets’ Sept. 22 regular-season finale at Citi Field, when the Mets, to a man, expressed a sense that they still had more baseball to play in Flushing this year. To do it, of course, they not only had to qualify for the playoffs but win the subsequent Wild Card Series, which wound up being against the NL Central champion Brewers in Milwaukee. They did both.

As the hits and runs stacked up Friday, the Citi Field roars grew louder, with the crowd not only believing in the runaway victory but maybe even the chance of the Mets giving them more games in Flushing this month. If the Mets can summon the resolve to steamroll the Dodgers after being smacked around for most of this NLCS, two more victories in L.A. certainly seem plausible.

For Sunday’s Game 6, they’ll send out Sean Manaea — who was solid before being pulled in the sixth inning of the Mets’ 7-3 victory in Game 2 — with Luis Severino lined up to start an all-hands-on-deck Game 7 on Monday night. It’s a tall task.

But one thing we’ve learned about these Mets: Anything is possible. They’ve been preaching that mantra since Memorial Day. And if they grind out two more wins at Chavez Ravine, the Mets will be in the World Series and back to Citi Field, where the party never stopped Friday night.

By David Lennon

dave.lennon@newsday.comDPLennon

David Lennon is an award-winning columnist, a voter for baseball's Hall of Fame and has covered six no-hitters, including two perfect games.