There's rivalry and then there's insanity.
The latter describes the hatred and yes, it's hatred between Louisville and Kentucky fans.
How else to describe what went down in a Georgetown, Ky., dialysis center this week, where a University of Louisville fan punched a University of Kentucky fan.
So, this afternoon, when Louisville and Kentucky tip-off the first game of the Final Four in the Superdome, New Orleans will be privy to the biggest game in the Bluegrass state's past 45 years.
Kentucky coach John Calipari isn't buying the hype.
No, for him, this game is about getting to Monday's final. It's not about exercising some sort of rivalry demon.
'The thing is this time of the year, rivalries do not matter,' Calipari said this week. 'Their fans, it matters. But it does not matter. You're playing a basketball game and whether the school is 15 miles away from you or 1,000 miles away, you're trying to advance.'
But, unequivocally, this game does mean more than just your typical national semifinal.
Louisville-Kentucky is something that most people don't, and can't, understand.
Let Rick Pitino, current coach of Louisville and former coach of Kentucky, explain.
'It all started with the racial lines in Louisville, Ky.,' Pitino said. 'We are the minority university. They (Kentucky) are the university of the privileged so to speak. That's where the rivalry really started.'
That's changed, of course, but the rivalry still has that bitterness.
'It was thrown out of the window when Tubby Smith became the first African-American coach,' he said. 'The hatred wasn't based on race any longer. That was over. I did everything humanly possible to recruit Louisville to end those lines because I didn't like it. The lines are no longer racially motivated. It's just pure hatred.'
For years, Kentucky wouldn't play Louisville.
The NCAA forced them to, however, by placing them in opposite brackets of the 1983 tournament. The Cardinals took that opportunity and took advantage, beating the No. 3-seeded Wildcats 80-68 in overtime in the regional finals.
It didn't matter that a season later, Louisville's season was bookended by losses to Kentucky.
Louisville had slayed the dragon in the biggest game between the two schools.
The biggest game, that is, until now.
Louisville's fans never really expected their team to make it this far. Kentucky fans have thought anything less than a national championship would be failure.
A win would give Kentucky a chance to win its eighth national title, bringing the Wildcats within three championships of UCLA's 11.
For the Cardinals, it would be an opportunity for just the program's second championship, which they'd certainly appreciated.
That would also mean they knocked out hated rival Kentucky.
And the Louisville players understand the significance of what's playing out along the Mississippi River.
'After the game in December (a 69-62 Kentucky win), it was just really hectic when we came back to the city,' Cardinals guard Chris Smith said. 'People were kind of looking down on us for losing. But right now, I would say this is probably the most amped up Final Four game in college basketball history.'
So, in fact, big that it started a fight in a Kentucky dialysis center.