As sports observers, in an effort to make ourselves feel that sports are more significant than they are, maybe, we often look for a moral component to weave into the narrative. We look at the field of play, of course, and then the life off the pitch. We search for a quality, or even just a moment of a perceived quality, where a player becomes emblematic of the evil guy you believe/want him to be.
Hating guys is often less trouble, since there's not the kind of risk that goes hand in hand with watching your beloved hero inevitably fail. In football, the guys I've always hated most have been good. Very good. Brady, Revis, Marino, Emmitt. Above all, we hate guys because they're good. Because they've made a habit of making our squad look like bitches. Because hating them is so much fun.
Hating a player for being good alone is rarely enough fun, though. Sometimes you just need a heel. The moral component of a guy being utterly terrible is often a necessity. Watching a sport, especially one as infuriatingly inconsistent with its rules as the NFL, is easier with a heel; a guy you can verbally douche upon with a moral righteousness to go with your over-consumption of Pabst and/or whiskey and/or ESPN. The heel allows you to swim in an Olympic-sized pool of sanctimony as we moralize over the lives of men we pay to subject themselves to repeated blunt force trauma. It allows all of it to seem more than what it probably really is: utterly insignificant and arguably inhuman in its brutality.