DURHAM _ Duke had the lead, the ball, the crowd, the momentum.

First place in the ACC was within reach, bringing the top seed in the ACC Tournament and a much-desired inside track to exotic Raleigh, where the RBC Center will host the first two rounds of the NCAA tournament beginning on March 21. The following rounds are to be played in Charlotte, a decidedly hospitable path to a berth in the Final Four.

The Blue Devils had won all 15 of their previous games this season at Cameron Indoor Stadium. On a chill night in early March their home arena was loud and feverish, packed with fans who grew progressively louder and more heated as Duke rallied from a 14-point deficit to surge ahead of North Carolina.

The action was appropriately fast-paced, aggressive, and physical, so physical a retired game official wondered afterward what had become of basketball’s free-flowing beauty.

Duke already had taken the measure of its archrival at Chapel Hill a month earlier. Now, with only five minutes and 44 seconds separating them from doing it again, the Devils spread themselves about the floor, circling for the kill as the crowd roared approvingly. “When the crowd gets in it, it’s tough to take that momentum away from them,” said UNC junior Marcus Ginyard.

But the Tar Heels drew motivation from the teams' first meeting, a performance that made them cringe when they watched it on tape. “We just came out with a stronger will defensively,” Ginyard said. “The first game, we allowed them to get everything they wanted offensively. We allowed them to get second shots. Tonight we were a little tougher about holding our ground.”

When push came to shove -- literally -- it was the top-ranked Tar Heels who seized control. They scored the final 10 straight points in a 76-68 win, thoroughly throttling Duke’s offense and aspirations. North Carolina improved to 29-2, the most wins ever for the program entering postseason play.

In the process the Tar Heels made an emphatic statement about themselves, their toughness and maturity. They also established, as they failed to establish for much of the season, that they can be a fearsome defensive unit.

“I think we have gotten better defensively,” said North Carolina coach Roy Williams, winner of three straight at Cameron. “We’ve been drilling it from the first day until yesterday. I don’t think anybody works on it any harder. Our kids have taken the challenge to try to be a really good defensive team. Sometimes you get lucky and they miss shots as well.”

Duke missed shots because UNC’s aggressive, helping defense was so disruptive. The Heels blocked 15 attempts, matching Maryland for the most this season by an ACC squad, and bothered many more. Danny Green alone blocked seven Duke shots, an individual high this year at North Carolina.

“I don’t know how it affected us, because we were taking it to the hole strong,” said Duke coach Mike Krzyzewski. “We need to come up with something when you go strong, we need to come up with some points.”

Particularly in the first half, UNC’s shot-blocking propensity made the Blue Devils hesitant. “They started double-pumping, things like that,” said UNC’s Ty Lawson. The guard, who missed the first meeting with Duke due to an ankle injury, reported improved maneuverability in contributing 10 points and 3 assists in 23 minutes. He promised full effectiveness by the conclusion of the ACC Tournament.

For the game, Duke shot .329 from the floor, nearly 16 percent below its season average. The Devils also committed 10 turnovers in the first half as the Tar Heels built a double-digit lead.

The evening began on a somber note, a moment of silence for Eve Carson, the UNC student body president murdered at mid-week. All the hype by ESPN and others about “bad blood” between schools seemed in particularly poor taste under the circumstances; the intensity of the athletic competition was, by comparison with the body blows delivered by real life, a happy trifle.

The much-anticipated game started with a quick 3-pointer by Gerald Henderson, seemingly presaging Duke's characteristic aerial assault. The Devils average 24 attempts from 3-point range per game, and lead the ACC in 3-pointers made.

But the usual screens, the penetrate-and-kick strategy, were well-anticipated by UNC. The Heels built their largest advantage, 29-15, with 5:18 left in the opening period, and still enjoyed a 42-31 lead at halftime. Only four, late 3-pointers by Duke’s Greg Paulus kept it that close. Green had 14 of his game-high 18 points in the half.

Predictably, Duke came out the aggressor in the second period, but didn’t catch North Carolina until Kyle Singler hit a three with 9:43 remaining to knot the score at 57.

The lead seesawed almost possession by possession for the next four minutes, and a classic finish looked to be in the offing. Then Duke grabbed the lead and the ball, and fell flat on its face.

“Maybe we just tried a little bit too hard there at the end,” Krzyzewski said of his sixth-ranked club, which fell to 26-4. “I don’t know. This comes with a little bit more maturity, playing in these type of games. Hopefully we’ll get a chance in the next few weeks to play in some other big games.”

Duke’s travails allowed Wayne Ellington to tie the score on a driving layup in halfcourt at the 3:02 mark, and Tyler Hansbrough to get the go-ahead basket on a follow shot nearly a minute later.

For all its supposed weakness inside, Duke handled Hansbrough. The junior finished with 16 points on 21 shots, lousy efficiency, and had 15 rebounds. For only the second time in his career, the likely all-time ACC leader in free throws attempted and made failed to earn a trip to the foul line.

But North Carolina’s ability to make a stand against Cameron’s emotional tide proved it is very much more than Hansbrough and a supporting cast.

“That’s the thing that’s going to make the difference late in the season,” Ginyard said, “is the fact that we have that mental toughness about us, where they come back and make a great run, they even take the lead, but we continue to stay poised, we continue to come right back at them and continue to play our game.”