DURHAM, N.C. -- When Duke started hitting from the perimeter, the Blue Devils ironed things out against rival North Carolina on Wednesday night.
"We have to work to get guys open," Duke forward Mason Plumlee said. "I thought we did a better job of that the second half."
With that, the ball started going in for second-ranked Duke, which overcame rough offensive stretches and foul trouble to turn away rival North Carolina 73-68 in the Atlantic Coast Conference game at Cameron Indoor Stadium.
The Blue Devils finally found their shooting touch, hitting 5 of 12 3-point attempts in the second half. Reserve guard Tyler Thornton hit three of the team's six 3-pointers in the game.
"We got those 3s and that (helped get us going)," Duke coach Mike Krzyzewski said on his 66th birthday. "I'm really proud of the grit my team showed."
Duke led 59-51 on Seth Curry's 3-pointer with less than five minutes to play and held on.
"We gave them too many good looks from 3s," North Carolina guard Marcus Paige said. "The second half, they got free a couple of times and knocked down some big shots."
That negated much of the good work the Tar Heels had done in taking a 10-point first-half lead. Duke is the ACC's leader in 3-point shooting, and that eventually showed.
The Tar Heels, who allowed 15 3-point baskets in Saturday's loss at first-place Miami, didn't yield a 3-pointer to Duke until nearly 16 minutes into the game.
"In my mind, it was not a matchup problem," North Carolina coach Roy Williams said of when the Blue Devils started connecting. "Their guys made some plays. They shot a couple that were difficult."
The Blue Devils also made 8 of 8 free throws in the last minute.
"Our guys have done so good in end-of-game situations," Krzyzewski said.
Plumlee and Quinn Cook scored 18 points apiece for Duke (22-2, 9-2), which is 13-0 at home this season. Rasheed Sulaimon chipped in 13 points and Curry had 11.
"We kind of struggled early in the game," Curry said. "They were real aggressive on me. ... Guys started making shots. You get confidence when you see one of your teammates making one."
Sophomore P.J. Hairston, making a rare start, scored 23 points for North Carolina (16-8, 6-5), which has lost back-to-back games for the second time this season. Reggie Bullock scored 15 and Dexter Strickland had 14.
With Plumlee saddled with his third foul less than a minute into the second half, James Michael McAdoo of North Carolina went to work in the lane and the Tar Heels established a 38-31 lead.
"They're deeper than we are, so you're worried about attrition," Krzyzewski said.
But Bullock ended up with his third foul with about 17 minutes to play, and Duke closed within 38-37.
Duke had its first lead at 42-41 on Curry's 3-pointer with 14:05 to play. The Blue Devils built the margin to 52-47, aided by a stretch of 7-for-10 shooting from the field.
North Carolina went almost five minutes without scoring, but Duke squandered several possessions by missing five shots in a row and committing a couple of turnovers. Bullock answered with a 3-pointer for the Tar Heels, trimming the deficit to 54-50 shortly after Plumlee picked up his fourth foul.
"We just have to do a better job of changing our cuts and moving without the ball," Bullock said.
North Carolina's attempt at completing a comeback was snuffed by six consecutive missed free throws.
"We needed them to miss a couple of those and we needed to make some of ours," Williams said.
The foul troubles began early, with both teams impacted. By the 5:57 mark of the first half, McAdoo and Plumlee each had two fouls. Cook and Curry had two fouls apiece barely 10 minutes into the game.
North Carolina, which encountered stumbles early in road losses at North Carolina State and Miami, carried a 33-29 lead into halftime after building a 10-point lead.
"By far the best (intensity) we've had this year," Williams said.
Duke had 12 field goals and 11 turnovers at halftime.
North Carolina, showcasing a tweaked lineup that included Hairston with his second career starting assignment, broke to a 17-10 lead. Hairston's point total and eight rebounds matched career highs.
Bullock's 3-pointer pushed North Carolina's edge to 28-18. Bullock had three first-half 3-pointers.
NOTES: This was the 150th consecutive meeting between the teams when at least one of them was ranked in national polls, dating to 1955. ... North Carolina freshman center Joel James, a 6-foot-10 reserve, didn't play because of symptoms of a concussion apparently suffered last week. ... Duke's victory made the home team 6-9 in this series since the 2005-06 season. ... Wednesday night's winning team is guaranteed nothing for the March 9 rematch in Chapel Hill. There hasn't been a regular-season sweep in this series the past three years.