Eighteen-year-olds aren’t supposed to make the Edmonton Oilers anymore. That’s all in the past, isn’t it?

Well, here’s something else that isn’t supposed to happen: Kailer Yamamoto, the first-rounder from 2017, isn’t supposed to be more NHL-ready than Jesse Puljujarvi, the first-rounder from 2016. Especially when Yamamoto stands five-foot-eight while Puljujarvi is six-foot-four, with a pro season in North America behind him.

But isn’t that why they play the games? So long shots like Yamamoto can show all us experts that we may be wrong — again.

“One of our best forwards again tonight,” assessed Oilers head coach Todd McLellan, after Yamamoto scored his fifth pre-season goal in a lopsided 6-2 rout by Carolina.

Puljujarvi, chosen No. 4 overall in ’16, had opened the night on a line with Connor McDavid and Pat Maroon. But his game just isn’t there yet, full of looping circles and stick-reaching checks. He’s 203 pounds, but Yamamoto has knocked more players off of more pucks this pre-season at 155 pounds.

By the second period, Yamamoto, picked 22nd in ’17, had taken his spot.

Clearly, Yamamoto is well ahead of Puljujarvi at this early juncture in their careers. That may change one day, but it won’t change by the time McLellan and general manager Peter Chiarelli have to name their 23-man roster to start the season.

“Never say never. That’s my motto,” said the feisty Spokane, Wash., native, who has a knack for scoring goals — in the pre-season at least. “Just keep putting my head down every day and working as hard as I can.”

If there is a shining example of how a rebuild never goes completely as planned, it is the Oilers. They stumbled and bumbled through years of fitful building, with their first No. 1-overall pick coming back in 2010 (Taylor Hall), and only this October do the Oilers open the regular season as a unanimous pick to make the playoffs.

Well, now we find out a resurgence doesn’t quite go the way we thought it would either. With a team-leading five goals and six points in four pre-season games, Yamamoto has had a better camp than Puljujarvi, and more than a few veterans as well.

“(Yamamoto) got pucks out when he needed to, he made plays. No glaring turnovers,” McLellan said after the loss to Carolina that dropped Edmonton’s pre-season record to 5-1. “He managed his shift length well, where we had other guys who milked it and went too long. Found a way to (deflect) one in for a goal. It’s been impressive watching him.”

But coach, your team is supposed to be past the point where the latest first-rounder can walk in and make the roster. Isn’t it?

“The 18-year-old isn’t supposed to step in and play, but when he continues to open your eyes,” McLellan admitted. “And you (media) guys wouldn’t keep asking me these questions if he wasn’t opening yours. He deserves the opportunity to keep on going.”

When camp opened, every single person inside this Oilers organization had Yamamoto returning to the Spokane Chiefs for his draft-plus-one season. Personally, I’d have bet you he would be sent down before the Oilers’ final pre-season tilt in Vancouver on Saturday.

But Yamamoto, who turns 19 on Friday, has been more than capable at even strength (he is plus-3). As a right-shot right-winger, he’s given the Oilers something that Jordan Eberle never could: a quick release on the power play. Like Mark Letestu, the fourth-line centre who stole Eberle’s job on the first power-play unit last season, Yamamoto doesn’t need to dust the puck off, or handle it a few times, before rifling a hard shot on net.

He has scored twice on one-timers from the left circle, a weapon that could just buy him a regular season game or two.

“You need a guy who wants to shoot the puck, and doesn’t shy away from it or (be deterred by) missing the net once or twice,” said centre Leon Draisaitl. “Connor and me, we like to pass. We really need a guy over there who can rip the puck.”

That guy wasn’t supposed to be the junior kid who learned to skate from Tyler Johnson’s mom in Spokane. Not this season, anyhow.

“Just being able to hang around (the Oilers players) day in and day out, it’s been a dream come true,” Yamamoto said. “I keep trying to work my hardest every day. Keep trying to make the team.”

There is no doubt that the NHL game has opened up to young, quick players like Yamamoto far more than in the past, and the juxtaposition of him passing by the big, powerful Puljujarvi is tangible evidence of that.

Now, we’ll reserve our final opinion until Yamamoto plays against entire lineups of NHL players. But it is time to admit that he has earned the chance to open the season in Edmonton.

Frankly, his coach can’t argue that point.

“I don’t care who plays on our team,” McLellan said. “We need 23 guys to wear jerseys. Whether he’s 18 or 38, we want to win, and it doesn’t matter to me what their names are or how big they are.

“If they can get the job done, then they should play.”