Kaapo Kakko went No. 2 in the 2019 NHL Draft and wears No. 24 on his back, but 18 is the number the Rangers and their delirious fan base should never forget.

That is his age.

By every account and through every eye test, the Blueshirts have themselves a special young man and an especially promising prospect in Kakko, the opposite of a booby prize following the Devils’ first-overall selection of Jack Hughes on Friday night in Vancouver.

The lottery victory that boosted the Rangers to their highest draft position in 53 years, since Brad Park went second-overall in 1966, energized everyone associated with the franchise. So did Kakko’s bravura performance for gold medalist Finland in the World Championships. So did the deals for righty defensemen Jacob Trouba and Adam Fox. The Rangers are on to Phase Two of their reconstruction process.

But just as it is essential for the coaching staff to work on Kakko’s development, it is critical for management not to get too far over its skis as it presents the teenager, who won’t turn 19 until Feb. 13, to New York. It is critical for the Blueshirts to manage expectations for Kakko out of the gate, the way they did not for seventh-overall Lias Andersson two years ago.

That is going to be the responsibility of John Davidson as president, to assert control over the marketing people whose job is to, well, probably the opposite of managing expectations. Business is business, but let’s face it, the Rangers aren’t exactly hurting for revenue. No one wants fried vendace on their face.

This isn’t meant to rain on the parade that has been a quarter of the century in the making. But it is important to be realistic. The Rangers have been chopping and pruning for a couple of years, beginning with the Derek Stepan 2017 draft day deal, and there will be more ahead in the not-too-distant future. Chris Kreider (I’d keep and extend him, but the team doesn’t seem to be leaning in that direction), Jimmy Vesey, Pavel Buchnevich, Vlad Namestnikov, Kevin Shattenkirk and Brendan Smith are also endangered species.

And by the way, Mats Zuccarello, Kevin Hayes, Kreider and Vesey received the second, third, fourth and fifth most ice time per game among Rangers forwards last year behind Mika Zibanejad. So a new generation not only is on its way, but also will assume more and more of the responsibility, perhaps even be force-fed to a degree by David Quinn, the coach who demands that young players earn their ice time.

Kakko has been a force. He zoomed up the charts like a Beatles’ single released in 1964 off his historic production in Finland’s Liiga, in which he established a record for draft-year players by scoring 22 goals to break the mark of 21 established by Aleksander Barkov in 2012-13. And we know that he is a hard-edged, north-south player who will give as good as he gets while blessed with exceptional finesse skills as well.

But he is 18, and no matter how broad his shoulders, he cannot be counted upon to carry the load, or even a couple of bricks of it. That would be ridiculous. The Rangers will need to give Kakko time to breathe and so will all the rest of us. Not only is he going to be asked to make the jump to the best league in the world as a teen, he is going to be asked, for better or worse, to assimilate into American culture.

Davidson would do cartwheels, even on his creaky knees, if Kakko becomes the dynamic player into which countryman Mikko Rantanen has developed for Colorado after having been selected 10th overall out of TPS in 2015. Granted, being selected 10th is different than being selected second. But Rantanen, who was rated the top European skater by Central Scouting in his draft year, would probably go fourth in a re-do behind Connor McDavid, Jack Eichel and Mitch Marner.

And while Rantanen recorded 87 points (31 goals) playing on the line with Nathan MacKinnon in the middle and Gabriel Landeskog on the left in his third full season, the fact is the right wing spent most of his rookie season with San Antonio of the AHL, getting into nine games (0-0=0) with Colorado. It isn’t Year One that necessarily counts, it’s the ones that follow.

Listen, Kakko is coming, so is Vitali Kravtsov, last year’s No. 1, so is Libor Hajek, so is Filip Chytil, so is Andersson, so is Igor Shesterkin, so is Yegor Rykov, so is Fox. It is an exciting time. But the operative word is time. As in, it is going to take some.

Kaapo Kakko is 18.