DURHAM, N.C. (AP) — Duke's most hated rival was running the Blue Devils off their notorious home court, so Mike Krzyzewski gathered them around at halftime and gave them a locker-room speech.

Not to fire them up. To calm them down.

Nolan Smith scored 22 of his career-high 34 points after halftime, Seth Curry finished with a season-high 22 and No. 5 Duke rallied from 16 points down to beat No. 20 North Carolina 79-73 on Wednesday night.

The Blue Devils (22-2, 9-1 Atlantic Coast Conference) trailed 43-27 in the final minute of the first half and were down 14 at halftime before clamping down on the Tar Heels, outscoring them 50-30 in the final 20 minutes to match the second-best halftime rally in school history and keep hold of first place in the league.

"It wasn't an X-and-O adjustment. ... They were too excited," Krzyzewski said. "'Nuts' is the word. What are you guys doing? It's not like, 'You know, you guys aren't playing hard.' They're playing hard. ... When you go like that, you're not coordinated, and it was more to get a coordinated effort on the offensive and defensive ends."

Tyler Zeller had 24 points and a career-high 13 rebounds, and John Henson added 14 points for North Carolina (17-6, 7-2), which had its five-game winning streak snapped and lost for the third straight time in college basketball's fiercest rivalry.

"To say it's extremely disappointing would be an understatement," North Carolina coach Roy Williams said.

Kyle Singler finished with 10 points on 3-of-17 shooting for Duke, but hit three important free throws in the final minute — including two with 25.2 seconds left to make it 75-70 after North Carolina had pulled within one possession.

Then, after Kendall Marshall hit a free throw to pull the Tar Heels within four with 17.2 seconds left, Smith beat everybody downcourt and soared for a breakaway dunk that sealed it, ensuring the Blue Devils would avoid their first loss at Cameron Indoor Stadium in almost two years and sending the storied arena into delirium.

Duke extended its NCAA-best winning streak at home to 33, and Smith called this one — and not last April's victory over Butler for the program's fourth national championship — the biggest of his career.

"This comeback win, how tough we were, how together we were and how great it feels now, I don't think anything can be better than this," Smith said.

Smith finished 13 of 23 and surpassed his previous career high of 33 points set a month ago against UAB. Curry hit two free throws in the final seconds to push his total past the 20 points he scored Jan. 27 against Boston College.

They teamed to help the Blue Devils deliver a comeback for the ages: Duke hadn't erased a halftime deficit that big to win since 1959, when the Blue Devils beat Navy after trailing by 14 at the break.

Duke was in the unfamiliar position of being dominated at home in the final seconds of the first half, with Curry's jumper at the 5-second mark starting the 18-6 run that made it a game again.

Curry started a 13-1 run with 10 1/2 minutes left to Duke up for the first time.

Curry reeled off seven quick points in little over a minute before Ryan Kelly delivered the game's only lead change. His 3-pointer put Duke up 57-55 with 9:15 left, and Smith's three-point play roughly a minute later stretched it to 60-55.

 Marshall, who took over at point guard following the departure of Larry Drew II, had six assists and one turnover, but was just 3 of 11 from the field.