CHAPEL HILL, N.C. -- Duke's short-handed roster full of youngsters proved it was tough enough to push through everything -- a deeper and more experienced opponent, a tough road environment, even a bit of adversity in the form of a key injury.
"We're a group of fighters," freshman Derryck Thornton said.
The Hall of Fame coach of the 20th-ranked Blue Devils isn't about to argue, either.
Grayson Allen scored 23 points, and Thornton came up with the clinching block on the final play to help Duke edge No. 5 North Carolina 74-73 on Wednesday night. Entering Wednesday, there was a difference of only 15 points in the teams' cumulative scores from their 89 meetings.
Allen hit a pair of free throws with 1:09 left for the lead. Then Duke (20-6, 9-4 Atlantic Coast Conference) came up with a pair of stops in the final minute, finishing strong after trailing most of the way while North Carolina's Brice Johnson put together a huge performance.
As coach Mike Krzyzewski put it, his Blue Devils "just hung in there." And by the end, a team that basically relied on five players the entire second half after losing Matt Jones to a first-half injury was the one making veteran plays on the road.
Not bad for a team that looked out of sorts only a month ago during a three-game skid that knocked Duke out of The Associated Press Top 25 for the first time since 2007. Now the Blue Devils have won five straight, including their past two by a single point against top-10 league opponents Virginia and UNC (21-5, 10-3).
This marks the first time Duke has won consecutive regular-season games against top-10 opponents when not ranked in the top 10, according to ESPN Stats & Information research. The only other times were during the 1990 NCAA tournament and 1980 ACC tournament.
"These kids have gotten so close," Krzyzewski said. "They've done an incredible job. At one time we had four freshmen and a sophomore out there. To have the toughness that they displayed with that youth is incredible."
With the victory, Coach K passed Dean Smith for most road wins against top-five teams (15) in NCAA history.
Duke got its first critical stop on a shot attempt inside in traffic by Kennedy Meeks. Then, in the final sequence, Johnson rebounded Allen's miss, and UNC pushed the ball up the court for a final shot without calling timeout in the final 20 seconds.
That's when Thornton blocked Joel Berry II's hurried shot in the lane. Allen rebounded the ball and flung it into the air to let the final seconds expire, then raced with the rest of the players straight to the Duke bench to celebrate.
Johnson had 29 points and 19 rebounds for North Carolina, which came in with a decided edge in size and depth. But Johnson got little help outside of Justin Jackson's 13 points, with the Tar Heels sputtering down the stretch after leading by eight with about 7 minutes left and Duke owning a 6.4 percent win probability, according to KenPom.com.
Johnson got just two shot attempts in the last 13 minutes.
"We were on the verge," he said.
It was a loss that coach Roy Williams called "tough to swallow," saying he told his team he should've called timeout before the final possession.
"I told them I was sorry, that I should've gotten us a better shot at the end," an emotional Williams said.
Duke: Krzyzewski said Jones sprained his left ankle "pretty badly," and it was unclear how long he would be out. ... The Blue Devils held UNC to 34 percent shooting and 27 points after halftime. ... The Blue Devils last took four straight rivalry meetings from March 2003 to February 2005. ... Freshman Chase Jeter played 3 minutes to spell Marshall Plumlee with foul trouble, but Duke stayed with the same five otherwise after halftime.
North Carolina: UNC finished with a 46-34 rebounding advantage, including 18 offensive rebounds that led to 25 second-chance points. ... UNC missed 12 of 13 3-point tries.
Duke freshmen Brandon Ingram (20 points) and Luke Kennard (15 points) had huge baskets down the stretch. Ingram, a prized recruit who passed on UNC, scored three straight baskets after the Tar Heels took their biggest lead at 68-60 with 6:49 left. He became the second Duke player after Jeff Mullins in February 1962 to record at least 20 points and 10 rebounds in his first career game against North Carolina, according to ESPN Stats & Information research.
Kennard came up with a 3-pointer at the 2:39 mark for a 72-71 lead, Duke's first lead since midway through the first half.
Berry and preseason ACC co-player of the year Marcus Paige struggled all night. Berry finished with eight points but went 2-for-12 from the field. Paige scored seven on 2-for-10 shooting, including 0-for-6 from 3-point range with three turnovers.
Duke travels to No. 18 Louisville on Saturday.
North Carolina hosts No. 11 Miami on Saturday.
ESPN Stats & Information and The Associated Press contributed to this report.
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