Roy Williams noted the challenges of defending Duke’s perimeter offense.

“You’re not going to stop Duke from shooting three-point shots because that’s what they practice every day,” Williams said. “It’s hard to stop us from blocking shots, or rebounding the ball or running the ball because that’s what we work on every day.

“But we’ve got to do a much better job of getting closer to shooter, trying to make sure that we get a hand up on the shot, not giving a pose after the ball has already been released. We’ve got to get closer. They’re really good.  Their offense is really good.”

Saturday night's game between the No. 4 Blue Devils and No. 6 Tar Heels could decide a No. 1 seed for the NCAA tournament. Duke took 36 three-pointers, hitting 14, in a 85-84 victory over the Tar Heels last month.

“Steve [Kirschner] and I were just talking about it on the way down here, their 36 three-point shots,” Williams said. “I took every one of those out, looked at it on tape, graded it myself, classified it myself and it’s like nine different categories.

“So that’s the good thing about – from their side – that’s the good thing about their offense because it does emphasize three-point shots. But a variety of different ways, with a variety of different guys screening and a variety of different guys spacing.

“So that means it’s really difficult to prepare … there’s not any one thing you can do to cover that.”