CHESTNUT HILL — With 6:24 remaining in a game Duke was already assured to win, Cooper Flagg sized up Boston College’s offense unfolding in front of him. As Dion Brown started to drive to the basket, Flagg trailed behind him.

After Flagg swatted the shot away, the referee immediately called him for a technical foul, presumably for something he said to Brown after the block. Flagg looked stunned. But he channeled whatever frustration he felt back into his play.

Twenty-four seconds later, at the other end of the court, Flagg knocked down a 3-pointer that stretched Duke’s lead to 25. He turned his back to the officials and shouted. Only the fans closest to him and elite lip readers know what he said. But it didn’t matter. The tone was obvious.

On a night when the BC crowd tried to jeer him early and Eagle guard Roger McFarlane literally smacked him across the face in the second half, Flagg stood defiant en route to the 88-63 win.

“There was a lot of energy coming off of that call, whatever that was – just a learning experience,” Flagg said. “I just wanted to come back, stay focused and knock down a shot.”

The 6-foot-9 wing has always been the heir apparent to the assembly line of lottery-bound players to spend a short time at Duke. But that sequence was also reminder. Some of the edgy competitiveness that made Christian Laettner, Bobby Hurley and J.J. Redick hated and feared superstars throughout college basketball runs through his veins too.

After back-to-back European stars were picked first in 2023 and 2024, the consensus No. 1 overall pick in the NBA Draft is a college basketball player again. Flagg was the reason that tickets were hard to come by at Conte Forum on Saturday and selling for well over $200. Not only is he the consensus No. 1 pick, but he’s a Maine native. A steady stream of four-wheel drive vehicles from as far as Aroostook and as near as York caravanned past all the moose crossing signs to see their new favorite son.

“What a special turnout,” Duke coach Jon Scheyer said. “The representation of Duke fans here has always been great, but this was the best I’ve ever seen and a lot of that has to do with Maine. That was a special thing to see.”

Like so many college stars playing close to home, the Newport, Maine product was a little overeager early, missing four of his first five shots. But he settled down quickly. For the fans who came specifically to see him, Flagg was worth both the length of the drive and the markup on the ticket.

He showed off his dunking, his shooting and some solid defensive instincts. Even the BC fans, who had been hoping to witness an huge upset will still be able to say they saw Flagg before he even turned 19.

“He should still be in high school,” Scheyer said. “For him to adjust his game that quickly is as good as I’ve seen.”

He had 28 points, five rebounds, four assists, two blocks and two steals in front of scouts from 14 NBA teams. He showed willingness to seek and play through contact going to the basket and made 9 of 11 free throws.

“It’s easy to talk about the scoring, but for me, it’s the blocks, the rebounds, the timely baskets, his feel for stepping up at the right time,” Scheyer said. “He just keeps getting better. He started off the year great, but he’s hit a new level with his assertiveness. Wherever you put him, he’s going to do something good.”

The next time Flagg plays in Boston, he’ll be facing the Celtics wearing a to-be-determined-NBA uniform. But he wasn’t ready to get that far ahead.

“This was my dreaming growing up to be in the position I’m in right now,” he said. “I’m just trying to enjoy it.”

Follow MassLive sports columnist Matt Vautour on Twitter at @MattVautour424.

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