Kentucky Coach John Calipari said of Duke’s Zion Williamson, who scored 28 points in his college debut: “I’m like, ‘Holy cow.’ ” (Andy Lyons/Getty Images)

The inevitable horror has arrived. The time has come. The birth date of Zion Williamson: July 6, 2000. And of R.J. Barrett: June 14, 2000. And then Tre Jones: Jan. 8, 2000. The world has reached that point when people born in the year 2000 not only can feed themselves, operate motor vehicles and speak full sentences without burbling.

No, they can craft outlandish, fearsome feats of collaboration and beauty such as the one Tuesday night from Duke’s freshman class of Williamson, Barrett, Jones and Cam Reddish, with Reddish benefiting from the extra learning of having arrived Sept. 1, 1999. They can beat No. 2 Kentucky in a season opener by a score that kept looking false until it landed on an implausibly true 118-84 and figure to spend a good while as unforgettable.

They can look rich in a maturity they weren’t supposed to have yet. They can astound. They can surprise Mike Krzyzewski when it’s hard to surprise Krzyzewski, the septuagenarian coach in his 39th Duke season.

“No matter how talented they are, you don’t know what they’re going to do, in this environment, against an outstanding team and a great program,” said Krzyzewski, who gabbed a few more words and then said, “They were magnificent tonight.” Shortly later he said: “I shouldn’t say I’m surprised at how well these guys played, ’cause I see them [in practice]. To play on this stage right away, against Kentucky, was a little bit surprising.”

Somehow, four scandalously young people who last year still roamed the hormonal hallways of high school in South Carolina (Williamson), Pennsylvania (Reddish), Minnesota (Jones) and Florida by way of Toronto (Barrett) wound up administering the most points against mighty Kentucky in 29 years, the biggest blasting of Kentucky in 10, the worst loss in the 26-season, three-university career of Kentucky Coach John Calipari and the third-worst loss ever by an Associated Press top-five team. With all of that, they went ahead and framed a new national season on its first night, establishing themselves as the mastodon whose No. 4 ranking looks too low by three and constructing a reference point that will hover from here to March and from coast to coast.

That would figure to replace the offseason hovering of courtrooms and wiretaps and illicit payments, giving the sport a fresh topic it might not deserve as spectacle and marvel triumph yet again.

Certainly the foursome arrived to Duke with their gaudy Rivals recruiting rankings — Nos. 1, 3, 5 and 14 nationally — and their seasoning born of the nomadic basketball travels afforded teenage sensations. Yet they played with a cohesion that betrayed their ages and the calendar, which supposedly still reads November. As they stop by Duke for a year of polish before ascending to the NBA, they’re supposed to spend November with the polish coming only in small and intermittent globs. Instead, they played with a maturity that might reflect these details: Reddish’s father played for VCU, Jones’s older brother played for Duke, Williamson’s stepfather played for Clemson, and Barrett’s father played for the Canadian national team in that tough 68-63 quarterfinal loss to France at the 2000 Sydney Olympics.

Knowledge of how to play seems to have gone imbued.

“The way they were talking on defense, moved the ball, and the way they were attacking the rim” all qualified as “very mature” in the view of Kentucky graduate transfer Reid Travis.

They dazzled repeatedly but also achieved smoothness. Barrett got 33 points, Williamson got 28, Reddish got 22, and Jones, the point guard, managed the thing with scarce glitches. “Four turnovers?” Calipari said of the Blue Devils’ total. “Either they’re the greatest ballhandling team in the history of basketball, or we’re not creating enough havoc.”

The 18,907 in Bankers Life Fieldhouse who grew sparse by closing time saw these scores: 34-13 halfway through the first half and 59-42 at halftime, then these second-half mirages: 66-42 (18:25), 80-49 (14:10), 88-54 (12:07). On the underside of those scores lay Kentucky, not some mid-level scrapper in town for a check. The severity itself became that thing you couldn’t stop watching. “When I looked up with eight minutes to go,” Calipari said, “I said: ‘We’re not calling a timeout, and if you foul, I’m taking you out. Let this thing run.’ ”

Long since an Instagram sensation, Williamson got his loud reaction upon pregame introduction and his loud reaction upon his big dunks, but those were the least of his skills. A 6-foot-7, 285-pound frame moving as his does can seem to be an optical illusion. On one drive, defenders fled because people tend to flee when they see something that large move that rapidly. On the next play, he rained in a soft, sweet three-point shot. On one roaring play with 14:38 left, he stole the ball under the basket Duke defended, then led a break and wound up threading a gorgeous pass to Barrett for the layup.

Krzyzewski: “That’s how he plays. He does that all the time.”

Calipari: “He got some shots off on big guys where we were trying to block, I thought that would bother him, and it absolutely did not bother him. We had a 7-footer in there and a 6-11, and he drove right at them and made them. I’m like, ‘Holy cow.’ ”

Williamson: “My nerves were pretty calm because in high school you’re very excited about it, but when you get to college, you just learn from the upperclassmen that if you get too excited, things will not go your way.”

Yeah, he’s a seasoned college veteran. He’s been there for weeks — plural.

Krzyzewski has had his freshman groups of Winslow, Okafor and Jones, or Bagley, Carter, Trent and Duval, but he had not seen an opener like this. It became hard to recollect all the talents to describe, harder still to guard them.

Krzyzewski said of Barrett: “R.J. in that first half was terrific. I mean, he was a man.”

Calipari credited Jones with “a steady game. I mean, he didn’t make a whole lot of mistakes.”

Krzyzewski said of Barrett: “He’s really tight — not tight as far as emotionally — but really tight on his shot even though he’s a movement player. You get that combination, it’s dangerous.”

The four had so many aggregate skills that they looked like eight.

“An interesting thing for our team,” Krzyzewski said, “is that we have four guys that can move the ball up the court, Tre, Cam, Zion and R.J., and they’re all playmakers. Zion was a point guard until he was in ninth grade. These guys can make plays for one another. And that’s an unusual mix.”

He said they’re “easy to coach.” He said they “really like one another.” He said, “The fact that they all came [to Duke] knowing that the others came kind of talks about their security as a player.”

As his descriptions backlit the collaboration and sparkling talent everyone had just seen, a nascent season had found definition, with Duke as the giant primed to spend the winter looming, further proof that, tough as it can be to take, people born in 2000 are all grown up.