For two periods, the score was normal. Then, came a wild and wacky third period that was totally unpredictable.

In what turned into an old fashioned shootout, the Rangers edged the Flyers 6-5 in overtime on Tuesday night at The Garden. Adam Fox scored 36 seconds into OT to give them the win on home ice.

The victory kept the Rangers a point up on the Bruins for first overall in the league. They became the first team to reach 100 points this season. Combined with a rare Hurricanes’ loss to the Penguins, they now lead the Metropolitan Division by three points with 10 games remaining.

By winning over the Flyers, who earned a point to stay in third place over the red hot Capitals (4-3 OT winners over the Red Wings), the Rangers rewarded coach Peter Laviolette with career win number 800. He became the seventh coach to reach the milestone.

When Fox beat Flyers’ goalie Samuel Ersson, Laviolette cracked a smile. Assistant coaches Phil Housley, Michael Peca, and Dan Muse congratulated him on the achievement. Laviolette then was all business by heading back to the winners’ locker room.

Fox’s career high 15th goal also clinched a playoff berth. The Rangers are officially in the postseason. During the postgame, Laviolette was quick to point out that it wasn’t a big deal. They knew they’d make it. It’s all about what happens ahead.

While Fox earned the game’s first star for posting the overtime winner and an assist to give him 63 points in 62 games to push his late Norris campaign, Alexis Lafreniere was the Rangers’ best player on the night. The former 2020 top pick was super throughout the game – scoring twice in a high scoring third period that defied logic.

Lafreniere now ranks second behind Artemi Panarin on the team in even strength goals. His pair both came at five-on-five to pull ahead of Chris Kreider. Of his 22 goals, 20 have come at even strength. Panarin leads the Blueshirts with 33 even strength goals.

The Rangers skated without three of their starting defensemen. Erik Gustafsson was the latest to go down to injury. Hartford recall Brandon Scanlin made his NHL debut. He logged 10:46 of ice time while partnered with Chad Ruhwedel on the third pair. Ruhwedel again had a solid game, even taking a key defensive shift with less than a minute left in regulation. The former Penguin hasn’t made any glaring mistakes.

They also were without Alex Wennberg, who missed the game due to a family emergency. His wife is pregnant. She’s due with the new baby soon. We’ll know more about the situation.

In another twist, Jonny Brodzinski scored a big goal to touch off a seven-goal third. The Rangers outscored the Flyers 4-3. Previously, they trailed 2-0 more than midway through the second until Mika Zibanejad scored a crucial power-play goal that gave them some momentum.

Before that, they were badly outplayed by a desperate Flyers team battling to make the playoffs. They lost a lot of battles and were sloppy defensively. For too long, the Rangers looked flat and uninspired. They were outskated by a wide margin.

In what was a scoreless first, the Flyers had the better of the play by firing 15 shots on Igor Shesterkin. However, most came from the outside. Aside from a Lafreniere turnover that led to Shesterkin denying Bobby Brink one on one, he didn’t have to work too hard in the period.

On the flip side, the Rangers had nine shots on Ersson. He made one strong glove save. Aside from that, he didn’t face much pressure.

Early into the second, the Flyers grabbed the lead. Taking advantage of a bad line change, Travis Sanheim moved the puck up for Travis Konecny. He then found Scott Laughton open for a wrist shot from the right circle that beat Shesterkin at 2:58.

On the play, the Rangers changed their forwards without getting the puck deep. That left Braden Schneider and K’Andre Miller without any help. Miller was too far over to the middle to recover and prevent Laughton’s shot. It was a total team breakdown.

Continuing to look out of sorts, the Rangers were two steps behind the Flyers. They were out of sync. When Vincent Trocheck went off for tripping Tyson Foerster, the league’s worst ranked power play connected to take a two-goal lead.

Defenseman Egor Zamula passed across for a Laughton one-timer that came right to Ryan Poehling in front for an easy put away that made it 2-0 with 8:21 left in the second.

At that moment, it looked like the Flyers would cruise to a victory. But an errant Foerster high stick on Fox in the offensive zone with just over five minutes left swung the momentum.

The Rangers remain one of the league’s most dangerous power plays. They entered tied with the Panthers for the fourth rated at 25.9 percent.

On the man-advantage, they had full control of the puck. Able to get it set up, they worked it around up top. Fox moved the puck across to Panarin at the left point. He then passed over for a Zibanejad wrist shot that went through a Chris Kreider screen past Ersson stick side.

Still trailing by one at the start of the third, the Rangers drew even thanks to Brodzinski. Only in the lineup due to the absence of Wennberg, Brodzinski took a pass from Kaapo Kakko and got his sixth of the season to tie it at 1:23.

Suddenly, with the crowd alive, the Rangers used the energy in the building to surge ahead. On a strong shift from Lafreniere and Zibanejad, whom Laviolette put together during the second, a fluky bounce led to Lafreniere scoring unassisted at 2:57. Zibanejad sent a puck towards the Flyers’ net that took a funny hop in front right to Lafreniere for a backhand that went in for a 3-2 lead.

After scoring three in a row, they spent an extended shift in the Flyers’ end. However, a Jimmy Vesey shot from a sharp angle missed wide to trap his teammates. That allowed Konecny to come in on a breakaway and score his 31st unassisted to tie it back up.

From that point, the period became unpredictable. With Zac Jones in the box for high-sticking, the Flyers turned over the puck inside the blue line. Konecny lost his balance. That led to a two-on-one between Zibanejad and Trocheck. He got the puck across for a Trocheck shorthanded goal that put the Rangers back up 4-3 with 10:26 remaining.

However, the lead was short-lived. On a smart lob pass from Morgan Frost, the puck came right to Owen Tippett at the Ranger blue line. He then broke away from a chasing Miller and whistled a backhand that banked off the goalpost and in. That came 2:11 later.

Laviolette decided to reunite his best line. The move worked. On a strong offensive shift, Panarin got the puck to Trocheck, who had the puck come right to Lafreniere for a quick shot past Ersson for his second of the game. His career best 22nd goal, put the Rangers back in front 5-4.

With the Flyers’ urgency increasing, a broken play led to Foerster jamming in a rebound to again tie it at five with 3:31 left in regulation.

In overtime, it didn’t take long for the game to end. On some hustle from Panarin in the corner to keep a play alive, that allowed Trocheck and Fox to play catch. Eventually, Fox came in and fired a wrist shot that went blocker side to give the Rangers the exciting 6-5 win in extras.

With three assists in the victory, Panarin now is up to 102 points. He became only the seventh Ranger to record 100 points in a single season. Jaromir Jagr was the last player to do it in 2005-06.

The other five Rangers include Mark Messier, Brian Leetch, Jean Ratelle, Vic Hadfield, and Mike Rogers.