It's a rivalry among hardcore fans of both teams based solely on a preseason fight between Christie and Fox and all the stuff said off the court. The rivalry often had little to do with play on the basketball court except for the 2002 WCF, where the end result was still the same. This "rivalry" was probably the most overblown rivalry of the past 20 years, though nothing can top the "rivalry" of the Red Sox and Yankees. And no, Sox-Yankees is not a real rivalry, it's just hate among fans. Yes, because the Yankees win every time, it's not much of a baseball rivalry, just one hell of an off the field and media-hyped rivalry.
You know you understand the viewpoint Brick, you just don't want to admit that any rivalry with the same income isn't much of a true rivalry.
And in case you're wondering, here's what rivalry means:
1 a : one of two or more striving to reach or obtain something that only one can possess b : one striving for competitive advantage
2 obsolete : COMPANION, ASSOCIATE
3 : one that equals another in desired qualities : PEER