When it is Christmas Eve and the air is filled with excited anticipation of unwrapping the gifts under the tree, you are not worrying about when the batteries will run out. That is the furthest thing from your mind. It is a holiday meant for instant gratification, even if some of those shiny new toys will be broken and discarded within a matter of weeks, if not sooner.

You know what it will be Thursday at the Garden leading into the 2019-20 season opener against the Jets of Kevin Hayes … er, Jacob Trouba … uh, Tyler Myers … well, then, Dustin Byfuglien? Ah, you get the point. It will be Christmas in October in Rangerstown. And why not?

Put aside the concerns about the second-line center spot or your questions about the defense. Stop obsessing over how much money in dead space the Rangers will carry next season in the aftermath of the Kevin Shattenkirk buyout. For a few hours, at least, stop fretting over the fact Filip Chytil and Vitali Kravtsov will need more time to apprentice before entrusted with assignments on Broadway.

It is Opening Night and Artemi Panarin is in a Blueshirt, so is Trouba, and perhaps even more fundamental than that, so is Kaapo Kakko. The last time a Rangers second-overall draft selection made his NHL debut was Oct. 23, 1968, when Brad Park of the draft class of ’66 was a minus-1 against the Oakland Seals. The last time a Rangers second-overall played on Opening Night was never.

It is Opening Night on Broadway and all good things are possible. Optimism is not only in the air, it is in the room. This isn’t about false bravado. It is about an organization on its way back following its mid-course correction only 20 months ago.

“There’s always excitement before the first game and it has always been that way for me, whether here or back when I was in Sweden,” said Henrik Lundqvist, who will start his 14th consecutive season opener. “You’re excited and also a little bit nervous to find out what the group will look like on the ice.

“The level of excitement might vary, depending on different circumstances, but I definitely feel more excitement than last year. I can feel that we are moving forward. Last year there was kind of a question of whether we were going forward or backward, still.”

The Rangers are going into a second straight season without a captain, the decision somewhat surprisingly not to give Mika Zibanejad the “C” and rather go with four alternates, including No. 93. We’re told the hierarchy did not want to introduce an added element to the mix that might interfere with Zibanejad’s steady yet dramatic ascension into a marquee first-line center, but there is no doubt he is perceived as a leader worthy of the assignment. If not sooner, count on next season.

“It’s an honor for me to be one of the four alternates,” Zibanejad told The Post. “Leadership on this team is not an issue. We are well taken care of in that department.

“I’m just excited. We’ve put a lot of work into this. Following all the moves over the summer, there was excitement just coming into camp and now after these three weeks, there’s even more of it. I have to say that I can remember all of my [five] opening nights, and I am more excited with every year that goes by.

“We have a lot in this room. The level of talent here, the additions we made, I think there’s no more using of — how should I say it? — excuses like there could have been last year, even though we didn’t want to use those excuses last year. I think we handled ourselves very well last year with the situation we were in, but the situation has changed.

“I know I’m excited to see us as a team.”

Chytil is not here and neither is Kravtsov. Ryan Lindgren will start with the Wolf Pack and so, too, will Yegor Rykov. Yes, Brendan Smith and Micheal Haley are on the roster and Vlad Namestnikov is still here and so too Marc Staal. But the Rangers are the only team to open with eight players 23-or-under and with five 21-or-younger on the roster.

This is a time to dream. The gifts are under the tree, wrapped in blue, red and white. It is Opening Night when everything is possible.

Christmas in October on Broadway.