Within minutes, you just know.
Whether it's the intensity of the first exchange, the way a guy who gets dropped immediately rallies or the times when the level of the competition equals (or surpasses) the significance of the event, it's clear that what you're watching is a fight you'll always remember.
Each decade has its classics. The 1970s had Ali and Frazier. The 1980s had Hagler and Hearns. And the 2000s had Corrales and Castillo. Meantime, in the 1990s, there were quite a few good ones as well.
We've gone back to the old tapes (thanks, YouTube) and put together a list of our 10 favorites from the decade that brought us Bill Clinton, Pearl Jam and the O.J. trial. Take a look and enjoy the memories, and feel free to drop some opinions of your own in the comments.