For decades, a win, or loss, in any given matchup between Duke and North Carolina has had the power to shape the next week, or month, or year, for the thousands of fans who wear different shades of blue, and bring two different worldviews to one of the most intense rivalries in sports.
On Saturday comes the 258th and most titanic meeting of them all - Blue Devils vs. Tar Heels in the Final Four, the first time that's ever happened. That it's happening in the 47th and final year of Duke coach Mike Krzyzewski's record-setting career, and that North Carolina could put an official end to that career, only adds to the tension.
"There are some portions of both fan bases that are scared to death to see this game for fear of losing it," said Wes Durham, the longtime play-by-play announcer who also hosts an ACC-themed sports talk show. "There are others who just say, 'This is the biggest stage this rivalry has seen, but it doesn't automatically mean whoever wins has leverage over the loser forever.' Only time will tell."
The coaches and players are doing their best to play this straight. A national semifinal being played on the floor of the Superdome is a massive enough moment in and of itself. Any opponent in such a high-stakes meeting is, by definition, an opponent demanding a team's full attention.
"It would always be important if it's North Carolina," Krzyzewski said. "It's the most important because if you win, you get a chance to play for the national championship. And that has to be your focus."
The messaging is completely valid. Listening to the "outside noise" - or, as Carolina coach Hubert Davis calls it "phone, family, friends and fans" - will not help either team prepare for this meeting.
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Yet, there are some things that simply cannot be avoided. Namely, the idea, baked into the DNA and geography of Tobacco Road, that these teams, and these schools, don't really like each other.
The rivalry shares features with others like it across the college landscape. One that comes to mind is the Auburn-Alabama showdown in football, an annual game that sets, or resets, bragging rights throughout the state for the ensuing 365 days, and often carries with it conference and national-title implications.
Durham said he's heard Auburn-Alabama described as "a football game that determines a culture war."
But where those schools are separated by 150 miles, and those teams play once a year, Carolina and Duke are next-door neighbors.
"They both need each other," Durham said. "The reason it's great is because both are so successful."
For North Carolina, this marks a record 21st trip to the Final Four. For Coach K, this is a record 13th trip to college basketball's biggest stage, which breaks a tie with UCLA legend John Wooden for most appearances by a coach.
Hard to tear down either program. That doesn't mean they don't try.
"They jab at each other," said Durham, whose father, Woody, was the radio voice of the Tar Heels for four decades. "My dad used to say, 'He's a Duke guy.' That's about as rugged a term as he could use."
A "Duke guy," by the most general definition of a North Carolina fan, is usually someone who's not from there. An elitist. Maybe a lawyer in waiting. Someone who looks down on people. He is, put simply, someone who loves Christian Laettner or J.J. Redick or Coach K.
North Carolina, meanwhile, is the fifth-ranked public institution in the nation according to U.S. News and World Report - a world-class university if there ever was one. But it is the state-chartered institution, one that is, frankly, bigger, less exclusive and easier to get into than Duke. Not even Michael Jordan, James Worthy or the late, great coach, Dean Smith, can change that.
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"People in North Carolina and UNC fans all over the country, they have an inferiority complex," said Redick, the 2006 lottery pick out of Duke, said in a recent episode of ESPN's 'First Take.'
Redick walked back the joke the next day, saying it was all in good fun.
Bottom line is, these are two great schools with two great basketball programs, each of which has the power to make the other's life much less pleasant at any given moment. And this is a very special moment.
The teams meet exactly four weeks after North Carolina walked into Cameron Indoor Stadium and put a beatdown on Duke in Coach K's final home game. It was supposed to be a celebration of a lifetime of coaching. Instead, a lasting memory of the day was Krzyzewski taking the mic after the 94-81 loss, apologizing and calling the entire performance "unacceptable."
There are those who had argued that that meeting - meeting No. 257 - was the most consequential game the teams had played in a rivalry that dates to 1920.
Now comes Game No. 258. Yes, there will always be next year. But given the stakes, the setting and the people and history involved, there won't be anything quite like this again.
"If you're Carolina and you won Coach K's last game at Cameron, and then you won the game to end his career," Durham said, "I could see how that might linger a bit."
North Carolina leads the series 142-115. Since Coach K arrived at Duke in 1980, the Blue Devils are 50-49. (50-47 not counting the two games Krzyzewski missed when he missed 1995 for back surgery.)
North Carolina is the sixth No. 8 seed to make the Final Four. Only one has won it all: Rollie Massimino's 1985 Villanova squad.
Duke is a No. 2 seed in the tournament for the 13th time. In 1991, Krzyzewski won his first national title as a 2 seed. The other four have all come with the Blue Devils seeded first.
Duke's Paolo Banchero, AJ Griffin and Mark Williams will almost certainly be in the NBA next year. North Carolina's top prospects are Caleb Love and Armando Bacot, though both are currently considered second-round prospects for the NBA draft if they choose to enter..