The North Carolina men's basketball team's domination of Clemson in Chapel Hill falls under that second category.
The Tar Heels have never -- that's right, never -- lost at home to Clemson. The scoreboard reads UNC 46, Tigers 0.
Clemson will take its annual stab at ending the skid tonight at 7, in a game televised by ESPN.
"I think it's very important to remember but also very important to make sure it's not over-emphasized," Clemson coach Larry Shyatt said. "These teams have not met this year. We will have a chance, unlike in most leagues, to meet twice. This will be one of them, and hopefully we will do the very best we can."
The Tigers (10-6, 1-2 in the ACC) face a tall order. UNC (13-2, 3-0) is riding a 10-game winning streak and playing its best basketball of the season.
The Tar Heels dismantled Marquette 84-54 on Saturday in their last nonconference game of the year, holding the Golden Eagles to 29.5-percent shooting.
"Sometimes stepping out of conference play is difficult to do," UNC coach Matt Doherty said, "But I thought our kids really reacted and responded very well."
Doherty hopes his team makes a similar transition back to ACC play. He doesn't want to have to explain how Clemson finally got out of Chapel Hill with a win.
The streak is fun for fans of both schools, but it's nothing but a headache for Doherty.
"I appreciate you bringing that up," Doherty said Tuesday to a reporter who asked about the streak. "I appreciate that. I was getting ready to eat lunch -- I think I'll put it off."
The pressure stems from the fact that the Tigers haven't just lost in Chapel Hill. They've lost big, averaging a
21-point margin of defeat at UNC.
Clemson has come within 10 points of the Tar Heels just one time since the 1981-82 season, losing 88-79 in 1998.
But if an upset is ever going to happen, perhaps this year is the year.
The Tigers have beaten two top-10 ACC teams on the road in the same week only once in school history. They did it in 1976, knocking off No. 5 Wake Forest on Jan. 17 and second-ranked Maryland on Jan. 21.
Tonight marks the 25th anniversary of Clemson's win against Wake. Eerily, the Tigers visit No. 8 Wake Forest on Sunday, the 25th anniversary of their win at Maryland.
Not that the Tar Heels care, though.
"We're not worrying about that string of victories," UNC center Brendan Haywood said. "Sooner or later, Clemson is going to have to get a win in here, and we don't want it to be this year.
"We just can't focus on it."
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