The best option to stop Knueppel is to put fellow freshman Drake Powell on him. Powell did a great job on Flagg for most of the game in Chapel Hill, and if Flagg sits, he'll be freed up to target Duke's new top offensive option.

For the third time this season, Duke and North Carolina are battling for their respective shades of blue. This time, in the semifinals of the ACC Tournament, the Blue Devils are out to a commanding 45-24 lead.

Duke’s Cooper Flagg, the ACC’s player and rookie of the year, appeared to injure his left ankle Thursday during the top-ranked Blue Devils’ ACC tournament opener in Charlotte. Flagg came down awkwardly on the foot of Georgia Tech’s Baye Ndongo while pulling down a rebound late in the first half.