The countdown, more than five years in the making, arrived at 10:10 of the second period of the Rangers’ exhibition opener against the Devils at the Garden on Wednesday.

That is when 23-year-old Igor Shesterkin, the Moscow-born 118th-overall selection of the 2014 entry draft, replaced Alexandar Georgiev in nets and thus made his quasi-varsity debut in Blue.

The goaltender has represented his native land in the World Championships. He has been in nets in KHL playoff games for SKA St. Petersburg.

Yet this …

“It is [such an] important game for me,” the Moscow native told The Post, without aid of an interpreter, before the game. “My first time at MSG. So I am a little bit nervous. I want to play really well. From the time when I was drafted, it has been my goal to play for Rangers.

“All the years, I have wanted this.”

Shesterkin did fine, surrendering one goal on 13 shots in 27:28 of work before being pulled for the extra attacker in the Rangers’ 4-3 loss. He seemed spry and technically sound, beaten only by Brett Seney’s third-period rebound off a blocker save on John Hayden from a sharp angle from the right.

He made a nifty left pad save on Nico Hischier with 5:10 remaining in the second period and soon after reached back into the crease to cover the puck after Nikita Gusev had rung one off the left post. It was a nimble and heady maneuver, and after all these years of waiting for the netminder, the crowd responded with chants of “Igor, Igor.”

You of course know Shesterkin has long been considered the heir apparent to Henrik Lundqvist. The line of succession is no longer so clear or immediate, given Georgiev’s excellent play last season. There is also the understood degree of difficulty in making the transition from the large European rinks to the North American game.

Still, nothing that has transpired since Shesterkin first reported for duty a couple of weeks ago has dimmed his future star or wounded the goaltender’s confidence.

“It’s my first time playing on smaller rinks, so it has been a little bit hard for me,” Shesterkin said. “I would like to be better every day, so I am working hard and am getting more comfortable all the time with this transition.”

Shesterkin, who will turn 24 on Dec. 30, has been working assiduously with goaltending coach Benoit Allaire. They communicate through goalie-speak, which is the same language used when Henrik Lundqvist made the transition from Sweden during his rookie 2005 NHL training camp.

“I remember that I was a little too aggressive my first couple of weeks before Benny pulled me back,” Lundqvist said. “I had to adjust. But I felt pretty comfortable, pretty fast.

“Benny allows you to play your own style and then he critiques and works with you on adjustments. It’s different for everybody. I talk to Igor, of course, and I like what I see from his talent and his work ethic, he has very quick feet, but I don’t give him technical advice.

“What works for me might not work for Georgie or Igor. It’s very personal.”

The additions of second-overall selection Kaapo Kakko and free agent signee Artemi Panarin have been the talk of Rangerstown for weeks. Kakko hardly looked out of his element, involved throughout in 20:50 of ice time that included 5:48 on the first power-play unit. Panarin ripped a one-timer home from the top of the left circle on a second-period power play, but left the match before the end of the period with a “mild groin strain” the Rangers said was not at all serious. We’ll see.

Just as we will see about Shesterkin, whose Broadway bow was somewhat overshadowed. After all these years, though, it was worth the wait. Now that the netminder is here, it is just a matter of waiting for the world-class athlete to adapt to his environment, whether in New York or through an apprenticeship in Hartford.

“This is the best league, so there have not been any surprises for me,” Shesterkin said. “Every player here wants to get better and works to get better. That’s the same for me.

“I like it here. I like the work. I like the guys. This is my goal. To play in the NHL. To play for the Rangers.”