(Photo credit: Bob Donnan-Imagn Images)

CHARLOTTE -- Duke freshman Cooper Flagg was unable to finish his first ACC Tournament game on Thursday, and it's up in the air whether the Blue Devils will use the conference player of the year Friday in the semifinals.

Flagg injured his left ankle with 2:46 remaining in the first half of Duke's 78-70 tournament quarterfinal win over Georgia Tech on Thursday and was helped off the court by teammates. He underwent tests on-site, and head coach Jon Scheyer said following the game that X-rays of the ankle were negative.

As for when Flagg might take the court again, that's a question with infinite variables. Friday's semifinals matchup is 'a long shot,' Scheyer said. The Blue Devils play the winner of the game Thursday between No. 4 seed Wake Forest against No. 5 seed North Carolina.

Kon Knueppel led a freshman-charged attack with a career-high 28 points after receiving a directive from Scheyer to pick it up in the second half. Knueppel responded with 22 points after intermission and Isaiah Evans added 14 for the game.

'It's not about one person, it's not about two people,' Evans said. 'It's about Duke.'

No. 1 in the nation with the NCAA Tournament a full week away, Scheyer did not speculate on the merits of holding Flagg out of the lineup the rest of the weekend. A win Friday would place the Blue Devils in the tournament title game Saturday night.

Duke also lost Maliq Brown in the first half with a separated shoulder, a repeat of the injury that caused him to play with a heavily wrapped left shoulder and upper arm on Friday. Brown, Scheyer said, was in 'a lot of pain' and left the stadium on a stretcher.

Flagg, the Atlantic Coast Conference Player of the Year, returned to the Blue Devils' bench in the second half under his own power without crutches or a walking boot.

Knueppel logged 39 minutes, had eight assists, five assists and quickly shifted into a different role comfortably when Flagg exited. He said the mentality for the team the next two days has to be 'next man up.'

'Kon's incredible, man,' Duke's Sion James said. 'With Coop out, more ball handling responsibilities fell on Kon, and Kon's one of the most poised, talented teammates I've ever played with.'

Flagg left his feet to gather a defensive rebound and landed awkwardly on his left leg, immediately grabbing his upper ankle and lower left shin area. He was ruled out of the game, the top-ranked Blue Devils' first in the conference tournament Thursday morning.

At halftime, ESPN's cameras showed Flagg being pushed in a wheelchair in the locker room area toward the X-ray room. He later was seen walking without assistance.

Georgia Tech led by as many as 14 in the first half and was up 26-17 when Flagg went out, and the Yellow Jackets took a 31-26 lead into the half over Duke. That was the largest halftime deficit of the season for the Blue Devils.

Before the injury, Flagg had two points on 1-for-7 shooting but had four rebounds, two steals and one blocked shot.

Duke missed its first 11 3-point attempts and shot just 2-for-16 from 3-point range in the first half but came out after halftime on a 21-9 run to take a 48-40 lead with 11:13 left in the second half.

Flagg came to his feet, but quickly lifted his left foot off the ground to balance on one leg and celebrate with teammates as the Blue Devils built a 54-43 advantage at the under-8 timeout in the second half.

The standout freshman, 18, is expected to be the No. 1 pick in the 2025 NBA Draft.

Flagg ranks among the conference's top 10 this season in points (third, 19.4/game), rebounds (eighth, 7.6), assists (eighth, 4.2), steals (10th, 1.5) and blocks (eighth, 1.3).

--Field Level Media