CHARLOTTE, N.C. -- Duke coach Jon Scheyer said it's a "real long shot" that freshman star Cooper Flagg will be able to play in the ACC tournament semifinals because of an ankle sprain.

Flagg rolled his left ankle in the first half of the top-ranked Blue Devils' 78-70 quarterfinal win against Georgia Tech. He hobbled off the court before heading to the locker room, then returned to the bench for the second half but didn't play again.

It came moments after defensive whiz Maliq Brown had to be helped to the locker room, his left arm hanging limply by his side after he again dislocated his left shoulder.

Scheyer said 6-foot-9 Flagg was already dealing with swelling and said he'd "have to be really convinced we should even consider seeing if he can go" in the semifinals Friday night.

Scheyer said X-rays showed no fracture for Flagg, the ACC's player and newcomer of the year, who averaged 19.4 points, 7.6 rebounds and 4.2 assists during the regular season.

"It's not about being ready to go tomorrow," Scheyer said. "That's not the most important thing for us. We've got to see if we can get him right for this run that we can make in the [NCAA] tournament.

"But I would have to be really convinced that we should even consider seeing if he can go [Friday]. He may not be able to go anyway. He probably won't be able to go anyway. But I think it's a real long shot, a real long shot."

Flagg wasn't available to speak with reporters afterward because he was receiving treatment for the injury.

It's too early to say whether the 6-foot-9 Brown will make it back at all. He was taken to a nearby hospital after dislocating his left shoulder again less than a week after returning from the injury. He plays a vital defensive role with his ability to switch screens, guard multiple positions and use his length to tally offense-disrupting deflections.

And just like that, Duke (29-3) now faces serious injury questions that threaten to linger well beyond however long the Blue Devils play this week in Charlotte.

"We worried about it after the game," Duke guard Tyrese Proctor said. "Obviously it's tough to see them go down. But it's basketball, it happens. It's unfortunate. We're going to get them right and they're going to be good and we'll just continue to play our game."

Duke was projected as the likely No. 1 overall seed in the NCAA tournament coming into the game after taking over the top spot in the rankings this week. The Blue Devils had won eight straight games before the ACC tournament.

The Blue Devils were trailing 26-17 late in the first half when Flagg went up for an uncontested rebound and appeared to have his left foot clip the foot of Georgia Tech's Baye Ndongo as he came down, causing his ankle to roll grotesquely and sending him crashing to the court grabbing at the joint with 2:46 left in the half.

Flagg hobbled back to the bench in clear distress, then bent over with his hands on the seats and pounded a chair with his right fist.

After sitting on the bench for a few minutes, Flagg got up and put his arms around two teammates and was taken to the locker room for observation. He was later shown in a wheelchair in the bowels of the Spectrum Center.

When Scheyer greeted each player with a high five or a hug at the locker room after the final horn, Flagg walked gingerly with his teammates before shaking hands with his coach as he filed into the victorious locker room.

"Cooper's one of the toughest guys I know," graduate guard Sion James said. "I haven't gotten a a chance to see him or talk to him but I really hope he's feeling a lot better."

Brown's injury had come moments earlier, at the 4:58 mark at the same defensive end of the court.

Georgia Tech guard Naithan George tried to dribble to his right at the top of the key before banging into Brown's left shoulder. He collected himself, did a jumpstep back and then charged forward to try to beat Brown into the paint. Brown reached with his left arm to try to poke the ball loose and immediately grabbed at the shoulder, sporting a black supportive sleeve, and doubled over in pain.

Trainer Jose Fonseca then had to guide the still bent-over Brown off the court and to the locker room.