(Photo credit: Bob Donnan-Imagn Images)

CHARLOTTE -- North Carolina will play in a game that might largely define its season Friday night in the Atlantic Coast Conference tournament semifinals.

Yet the Tar Heels (22-12) aren't likely to be the main storyline when going against top-ranked Duke.

The Blue Devils (23-9) might be without ACC Player of the Year Cooper Flagg, the most highly regarded player in college basketball this season. Flagg sprained his left ankle during Duke's quarterfinal victory against Georgia Tech on Thursday after landing on an opponent's foot in the first half.

He didn't return to action, leaving him with a season-low two points. His status for the North Carolina game seems iffy at best from the Blue Devils' perspective.

'I would have to be really convinced that we should even consider seeing if he can go (Friday),' Duke coach Jon Scheyer said. '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.'

No. 1 seed Duke rallied for a 78-70 victory after trailing by 14 points in the first half.

'I think it just shows that we're a real team,' Duke guard Isaiah Evans said. 'It's not really about one person or two people. It's about Duke. Duke is going to handle business all the time.'

Fifth-seeded North Carolina, which won for the second day in a row on Thursday, defeating fourth-seeded Wake Forest 68-59, has plenty at stake. A victory against Duke possibly would be enough to secure an at-large spot in the NCAA Tournament -- and leave the Tar Heels one victory away from an automatic berth because they would be in the league tournament final.

'Playing Duke is an opportunity to play against the No. 1 team in the country,' North Carolina coach Hubert Davis said. 'Obviously, they're playing extremely well.'

Duke defeated North Carolina twice during the regular season, including an 82-69 victory on Saturday on the road despite trailing in the second half.

The Tar Heels have received recent strong contributions from senior guard RJ Davis, who a year ago was named the ACC Player of the Year. He scored 23 points against the Demon Deacons.

'There is urgency because he has no more eligibility left,' Hubert Davis said. 'But there's also a sense of calmness and steadiness that this team has needed all year long, especially in situations like late game.

'Having a guy like RJ that's been there, done that before and being able to draw on his experience and how calm he is and be able to execute under pressure just helps out our team so much.'

RJ Davis has scored 20 or more points in four of North Carolina's past eight games.

Aside from Flagg, the Blue Devils are expected to be without reserve forward Maliq Brown, who exited the Thursday game prior to Flagg after aggravating a left shoulder injury.

'He's going to miss time no matter what,' Scheyer said.

Freshman Kon Knueppel picked up the slack with a season-high 28 points against the Yellow Jackets.

'For Kon, he plays at a great pace,' Scheyer said. 'He has great size, which allows him to score over the top or pass.'

This will be the first time for Scheyer and Davis as head coaches that the Duke-North Carolina rivalry is contested in the conference tournament.

North Carolina is 24-8 in ACC tournament games in Charlotte.

--Bob Sutton, Field Level Media