PHILADELPHIA — Just when the Philadelphia Phillies were on life support and preparing or their last rites, they jumped up, yanked the cord out of the wall and had an entire city screaming in sheer elation.

The Phillies, stealing a page out of the New York Mets’ cardiac kids manual, pulled out a dramatic 7-6 victory to tie this electric best-of-five National League Division Series at 1-1.

The hero was Nick Castellanos, viciously booed earlier in the game, who hit a two-out, walk-off single in the ninth, completely the comeback.

The Phillies came back from a 3-0 deficit in the seventh inning by hitting 856 feet of homers on three pitches.

They came back from a 4-3 deficit in the eighth inning by playing small ball, with a walk, single, and a two-run triple by Bryson Stott off Mets closer Edwin Diaz for a 6-4 lead.

And after coughing up the lead in the ninth on Mets third baseman Mark Vientos' two-run homer, they rallied one more time in the ninth on Castellanos’ heroics.

Just like that, the Phillies are alive and well, and headed to New York to play Game 3 of the NLCS at Citi Field.

The Mets, meanwhile, are thrilled just to get back home again.

They left town two weeks ago having no idea whether they’d play at Citi Field again this year.

They had to survive a doubleheader in Atlanta just to guarantee they would play in the postseason. They had to hit a 9^th-inning homer in Milwaukee just to get out of the National League wild-card series

Now, after leaving New York on Sept. 22, they are returning on Tuesday for the first time in 16 days, and two victories away from their first NLCS since 2015.

If the Mets don’t advance, they’ll be haunted all winter by this night and the decisions that backfired.

The Phillies were completely shut down by starter Luis Severino for the first 6 ⅔ innings, with the sellout crowd of 45,679 showing their disgust by unmercifully booing them.

Trea Turner kept the inning alive with a two-out single to left.

That brought up Bryce Harper, and a quick visit to the mound by Mets pitching coach Jeremy Hefner. They discussed strategy, and decided to challenge Harper.

Turned out to be a mistake.

Huge mistake.

Severino got ahead of Harper, 1-and-2, and just missed on a 98.6-mph fastball.

He came back with a 99-mph fastball, and watched Harper send it 431 feet over the center-field fence for a two-run homer. The place erupted as Harper circled the bases, crossed home plate, and thrust his right arm into the air, and again and again.

Two pitches later, Castellanos, sent an 86.4-mph slider over the left-field fence.

Tie game.

Bedlam.

Instead of unravelling, the Mets grabbed their bats, went back to work, and watched Brandon Nimmo carer homer over the right-field fence, giving a 4-3 Mets’ lead.

Mets manager Carlos Mendoza, going for the jugular, gambled and called upon closer Edwin Diaz for a seven-out save.

He got two outs. And no more.

Diaz struck out Kyle Schwarber to end the seventh and Trea Turner to open the eighth, but it was the last batter Diaz would retire.

He pitched around Bryce Harper and walked him. Castellanos singled to right field, advancing Harper to third base.

And Stott then delivered what appeared would be the knockout punch with a two-run triple into the right-field corner, giving the Phillies a 5-4 lead, which became 6-4 when J.T. Realmuto hit a soft chopper to Vientos that he wasn’t able to handle.

But these are the Mets, who have produced 44 comeback victories this season, and have tormented the Phillies’ bullpen this season.

So, who else, but Vientos once again, hitting a two-run homer that landed in the front row of the left-field stands, tying the game at 6-apiece.

But in the bottom of the frame, Mets reliever Tylor Megill issued back-to-back two-out walks to Turner and Harper – setting up Castellanos' walk-off hit.

Just like that, it was an instant classic.

"They have a slow heartbeat and they understand situations and they just keep battling. It's a very resilient club," Phillies manager Rob Thompson said after the game. "And you can see the same thing with the Mets, they're not going to quit either.

"This is shaping up to be a classic battle."

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Here's how Sunday's game unfolded in Philadelphia:

Nick Castellanos hits walk-off single to give Phillies 7-6 win

Tylor Megill walked Trea Turner and Bryce Harper with two outs, setting up Nick Castellano' walk-off line drive into left field to even the series.

Mark Vientos home run ties it in ninth inning

Mark Vientos hit a two-run homer off Matt Strahm in the top of the ninth to tie the game 6-6, a stunning turn of events after the Phillies had rallied back to take a two-run lead in the bottom of the eighth.

It was Vientos' second home run of the game after his two-run shot in the third inning opened the scoring.

Phillies go ahead with Bryson Stott’s two-run triple

Birthday boy Bryson Stott hit a two-run triple to right off Mets reliever Edwin Diaz, giving the Phillies a 5-4 lead in the bottom of the eighth. JT Realmuto followed with an RBI fielder's choice to make it 6-4, a critical insurance run with the Phillies needing to get three more outs.

Phillies squander seventh-inning chance

Edwin Diaz replaced Jose Butto with two outs and two on in the bottom of the seventh, striking out Kyle Schwarber on a checked swing to end the threat.

The teams are a combined 0-for-11 with runners in scoring position as the game heads to the eighth inning with the Mets up 4-3.

Brandon Nimmo restores Mets lead with home run in 7th

After the Phillies got two homers in the bottom of the sixth to erase their 3-0 deficit, Brandon Nimmo responded in the top of the seventh with a two-out solo homer off Orion Kerkering, putting the Mets ahead 4-3.

Phillies tie it with back-to-back homers

After getting the first two outs in the bottom of the sixth, Luis Severino gave up a single to Trea Turner followed by a monstrous two-run homer to Bryce Harper that made it 3-2, finally getting the Phillies on the board.

Nick Castellanos followed with a solo home run against Severino, tying the game and sending the crowd into a frenzy.

This game heads into the seventh inning tied 3-3.

Pete Alonso home run extends Mets lead in sixth

Pete Alonso hit an opposite-field solo home run to lead off the top of the sixth against new Phillies reliever José Ruiz, providing the Mets with a crucial insurance run and a 3-0 advantage.

Mets lead 2-0 through five

Mark Vientos' two-run homer in the third remains the game's only scoring, with Luis Severino and Cristopher Sanchez trading zeroes at Citizens Bank Park.

Reliever José Ruiz will replace Sanchez to start the sixth for Philadelphia.

Mark Vientos home run gives Mets third-inning lead

Mets third baseman Mark Vientos hit a two-run homer in the top of the third to open the scoring, bringing home Francisco Lindor who had singled with one out.

Vientos had a breakout season playing every day for the Mets, finishing the regular season with 27 home runs. He was especially dangerous against lefties like Phillies starter Cristopher Sanchez, batting .300 with an .884 OPS vs. southpaws in the regular season.

It’s 2-0 heading into the bottom of the third.

Phillies work around error in second inning

Third baseman Edmundo Sosa’s throwing error gave Jose Iglesias an extra base on an infield single to lead off the top of the second, but Cristopher Sanchez got J.D. Martinez to pop out to second, Starling Marte to line out to center and Francisco Alvarez to ground to first, ending the frame.

The Mets are already 0-for-5 with runners in scoring position.

Mets vs. Phillies Game 2 underway

Phillies starter Cristopher Sanchez worked around Mark Vientos' one-out double in the top of the first, getting Brandon Nimmo and Pete Alonso to fly out to center to end the threat.

Mets pitcher, lineup for NLDS Game 2

Starting pitcher: Luis Severino

1. Francisco Lindor (S) SS

2. Mark Vientos (R) 3B

3. Brandon Nimmo (L) LF

4. Pete Alonso (R) 1B

5. Jose Iglesias (R) 2B

6. J.D. Martinez (R) DH

7. Starling Marte (R) RF

8. Francisco Alvarez (R) C

9. Harrison Bader (R) CF

Phillies pitcher, lineup for NLDS Game 2

Starting pitcher: Cristopher Sanchez

1. Kyle Schwarber (L) DH

2. Trea Turner (R) SS

3. Bryce Harper (L) 1B

4. Nick Castellanos (R) RF

5. Bryson Stott (L) 2B

6. J.T. Realmuto (R) C

7. Brandon Marsh (L) LF

8. Edmundo Sosa (R) 3B

9. Johan Rojas (R) CF

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This article originally appeared on USA TODAY: Phillies vs Mets highlights: Castellanos wins crazy NLDS Game 2