BROOKLYN– The Atlantic Coast Conference Tournament here at Barclays Center have already been filled with and dramatic moments and brilliant performances in its first trip to the borough.

But it is hard to believe any will be more epic Friday night’s semi-final match up between 14th-ranked Duke (25-8) and sixth-ranked North Carolina (24-8). The Blue Devils rallied from 12 points down in the second half, getting an emotional lift from a revitalized Grayson Allen, to defeat Louisville, 81-77, here Thursday to set up Round 3 of the latest edition of this fabled Tobacco Road rivalry. The two teams have split their first two games, with Duke winning at Cameron and Carolina winning at the Dean Dome.

“We’re two of the great programs,” Duke coach Mike Krzyzewski said. “We’re accustomed, they’re accustomed to playing in building that has a lot of energy, for or against them. So to be in that moment, the people who are in the stands, they have a chance to enjoy that because those moments don’t happen all the time. Our two programs have created a lot of them.”
The neighboring schools, located 12 miles apart, own this event. Duke has won 19 ACC tournaments, one more than Carolina.

The Tar Heels cruised to a victory over Miami in its quarterfinal, looking every bit the national championship contender.

Duke made a huge statement against the Cardinals, reasserting themselves as a team that would reach the potential they had in preseason when they were voted No. 1 in the pre-season polls.

“So that was a quarterfinal game. Holy mackerel,” Duke coach Mike Krzyzewski said. “Wow. That was a big time game. We’re so pleased and proud of the win because we beat a heckava team and a team that could win it all.

“We made some shots and played our hearts out. They played their hearts out. We hit a couple more shots than them. I don’t know how you split hairs on that game. Both teams played so hard. That was a heck of a game, just in case you didn’t know that. I would hope you would know that.

“Hopefully, we have some gas in the tank here as we push on.”

The Devils has been involved in a tumultuous season that crystallized when Krzyzewski suspended Allen indefinitely before league season when he tripped an Elon player. The discipline came about 10 months after Allen tripped two players– one from Louisville, the otehr from Florida State– and received no punishment, from either Duke or the ACC.

This time, Krzyzewski suspended Allen for one game, leading to increased scrutiny of a talented, lightning rod player who received two technical fouls in the previous two games and went scoreless in 13 minutes during the Devils’ victory over Clemson in a first round tournament game.

Allen, who was nursing a sore knee, returned to form against Louisville, coming off the bench to score 18 points to supplement 25 points from forward Jayson Tatum and 24 from Luke Kennard. “We really needed a spark off the bench and I didn’t think I did a good job of that in the first game,” Allen said.

Allen was booed by opposing fans every time he stepped on the floor, especially with so many Carolina fans in the stands. Duke fans tried to drown out the vocal criticism with cheers.

Allen has learned to suck it up when the heat is on. He scored 10 points in a six-minute stretch to energize an emotional comeback. Allen was fouled shooting a 3 with 8:58 left, As he shot his free throws, there were boos. After every make, there were cheers.

“God bless everyone,” Krzyzewski said. But energy produced more energy.”

Allen cut the lead to to 64-61 by the time he was done and then went back to the bench where his teammates got to their feet to greet him with high fives and pats on the back. Krzyzewski used the moment to greet Allen with a bear hug. “I love Grayson,” Krzyzewski said. “Grayson, I got his back all the time. And everyone in his program has his back all the time. The public eye on our program on our program is a blessing and a blessing can be a curse. So we have to be able to deal with all of it.”

Duke took the lead for good when Kennard and Tatum hit back to threes to give the Devils a 78-73 lead with 2:04 to play. Despite the talent discrepancy, Louisville could have easily won this game if they had only made their free throws. Rick Pitino’s Cardinals shot just 15 for 26 from the line and their misery was compounded when they made just 4 of 21 three point attempts and struggled when Duke went zone, letting a 61-49 slip away.

“When you know you’re supposed to win a game, it’s just disappointing, especially when you lose the way we did,” Louisville guard David Levitch said “We were in control. We lost a game because we didn’t do the things we can control and that’s what hurt us.”

Both these teams are good enough to make deep runs into the tournament. They both look like three seeds heading into this weekend. But Duke’s future is tied to Allen and how he continues to handle self imposed pressure.