Three minutes had not yet bled off the clock on the massive cylindrical scoreboard that hangs over the Madison Square Garden ice and the Rangers were already facing their worst nightmare:

Jack Hughes with the puck on his stick on a breakaway, no one in front of him other than Rangers goalie Igor Shesterkin.

The last time the Devils’ 21-year-old wunderkind winger had a breakaway with only Shesterkin standing between him and a goal was in Game 1 when Hughes was awarded a penalty shot.

He scored that night with relative ease, deeking the Rangers’ world-class goalie to the ice and putting the puck in the back of the net.

That goal didn’t matter so much, though, because the Devils were trailing 4-0 in the third period that game and the Hughes tally was a mere garbage-time footnote.

The Hughes goal 2:50 into Game 4 on Monday night?

That was a big one.

It was a rapid game-changer — for the game and for the series, which is now tied 2-2 after the Devils’ 3-1 win over the Rangers in front of a stunned Garden crowd that began the night stoked and loud and spent much of the rest of it emitting nervous energy, with a lot of groaning and even some boos raining down on the home team.

Watching the goings-on at the Garden on Monday night left you shaking your head that, just three days ago, this same Rangers team owned this series, was dominating the Devils, who looked unsure of themselves and a bit rattled by the big playoff moment in the first two games.

The Hughes goal, his third of the series, was significant because it provided further evidence that the Devils’ star players have come alive.

That was something that New Jersey coach Lindy Ruff called for before Game 3, which was won by the Devils, 2-1, thanks to a second-period Hughes equalizer on a power play and a game-winner in overtime from Dougie Hamilton.

Hughes is, by far, the Devils’ biggest star. As he goes the Devils go.

“He’s a fun player to watch,’’ Ruff said after Monday’s game. “Night in night out, he’s doing special stuff. I think his play away from the puck tonight deserves a lot of credit, too, because he was up against some seasoned guys that he knew he had to be good defensively, and I thought he really was.’’

Interestingly, Ruff said he thought that goal on the penalty shot was a key precursor to Hughes’ goal in Game 4.

“I referenced that as a good moment for him, knowing that he can go in and finish,’’ Ruff said. “Then he got another opportunity like that tonight. He’s trying to lead by example.’’

And lead he did.

“It was huge,’’ Devils defenseman Jonas Siegenthaler said of the goal. “When Jack’s out there, you want to get him the puck. When he has the puck on his stick and he’s in the O-zone, most of the time something good is going to happen.’’

It was Siegenthaler who sent a backhand clear of the loose puck out of the New Jersey goal crease and onto Hughes’ stick for the breakaway.

Ruff isn’t one for making bombastic public comments to push his players’ buttons. He falls more on the low-key and understated side than being a bang-the-table guy to get his message across.

But, after his team was outscored 10-2 in the first two games in New Jersey, Ruff’s feathers were ruffled and he spoke out about his star players who hadn’t been producing. This wasn’t Ruff calling his stars out as much as it was him simply stating the obvious.

Hughes, who led the team with 43 goals and 99 points in the regular season, entered Game 3 with one goal, which came on that freebie penalty shot with the Game 1’s outcome already decided. He scored the equalizer in the Devils’ 2-1 overtime win in Game 3 and then there was Monday night’s tone-setter.

“They know they have to produce,’’ Ruff said in reference to his star players in advance of Game 3. “There’s no secret that, in the playoffs, your top players have to be the guys [who] get it done for you. Those guys have to make the difference for us.’’

The Rangers roughed Hughes up in the first two games, bottled him up and prevented him from using his majestic skating ability to his advantage. Hughes was frustrated.

“We got whacked two games in a row and the last thing we want to do is stand and talk in front of you guys,’’ Hughes said to reporters after the Devils’ Game 3 win. “But it’s a better feeling now.’’

Monday night was even better for Hughes and the Devils.