Five observations from Duke's loss in the semifinals of the ACC tournament

Duke's six-game winning streak against North Carolina in the ACC tournament was snapped late Friday night, as the 12th-ranked Tar Heels took down the fifth-ranked Blue Devils 74-69 in the semifinal round.

Duke was coming off a big 88-70 win over Notre Dame on Thursday, in which the offense looked great at times. But that wasn't the case Friday.

Duke shot 41 percent from the floor overall and 26 percent from beyond the 3-point line.

The game got weird early. Senior guard Grayson Allen was called for a flagrant-1 foul for hip checking North Carolina's Garrison Brooks. The call resulted in two free throws for the Tar Heels and the ball.

And freshman point guard Trevon Duval, who had been crucial to Duke's success recently, rolled his ankle in the first half. He had it re-taped on the bench, and played through it. But he did not look the same.

Duke was hoping to win its second consecutive ACC tournament title, and 12th in the last 21 years.

With the loss, Duke's case for a No. 1 seed in the NCAA tournament becomes a lot harder to make.

Here are five observations from the game:

1. Duke was cold from the outside

Duke could not buy a shot from behind the 3-point line. Credit North Carolina. There were very few open 3-pointers for Duke to take. The Tar Heels contested most of those shots and made it hard for the Blue Devils.

Duke finished 6-for-23 from behind the 3-point line, which was 26 percent.

2. Turnovers

Turnovers have been a theme for Duke in many of its losses. The Blue Devils had 18 turnovers on Friday, one shy of a season-high. The Tar Heels scored 21 points off those turnovers, and Duke had 17 fewer shot attempts at the basket. Duval had five, Allen had four, and freshman Marvin Bagley III had four.

"We're not going to win against a team of that caliber if we turn the ball over 18 times," said Duke coach Mike Krzyzewski.

3. Offensive rebounds a problem

It looked like a replica of the first time Duke and North Carolina played, which the Tar Heels won 82-78 on Feb. 8. Duke would make a good defensive stop, and North Carolina would rebound its own miss. It happened again on Friday.

North Carolina was relentless on the offensive glass. The Tar Heels tipped out many rebounds to extend plays. While the Tar Heels did not always turn those offensive rebounds into points, they took time off the clock.

"We didn't execute with all five guys rebounding," Duke freshman Wendell Carter Jr. said. "But it's just a learning experience. We've got a possible six games left so we're just looking forward to the next game."

4. Injuries will be a concern for Duke

Duval rolled his ankle early in the first half of Duke's game against UNC. He had to be helped off the floor and got it re-tapped before going back into the game. X-rays after the game came back negative, Krzyzewski said.

He looked limited at times and finished with zero points, seven assists and five turnovers.

On Thursday, Krzyzewski revealed that Carter was dealing with a foot injury of his own. Carter said Friday he also had rolled his ankle.

For the most part this season, Duke's starters have been healthy. Bagley missed four games in February, but has returned to full health. No other starters have missed time with injuries.

5. Defense was not very good

The Tar Heels had many open shots in Duke's zone defense. They didn't always make those shots - the Tar Heels shot 39 percent from the floor - but the shots were there.

North Carolina also scored 34 points in the paint.

"They did a great job of getting the ball in the middle," Duval said. "When the ball gets into the middle like that, it's hard to stop them because it breaks down our zone."

Krzyzewski had a different opinion about the defense. He noted that Duke only gave up 74 points to a good UNC team.

But the Tar Heels' 74 points was the most Duke has given up in the past nine games since it played North Carolina on Feb. 8.

This story was originally published March 10, 2018 at 1:11 AM with the headline "Five observations from Duke's loss in the semifinals of the ACC tournament."