For any San Diego Chargers fan that has been a fan of the team long enough, you almost certainly feel the most pain when they lose to the Oakland Raiders. The reasons for this are many. The Raiders have long been one of the dirtiest (and most penalized) teams in The League. This was by design. Al Davis loved fielding a team like that. They have one of the largest and most obnoxious (stabbing people is obnoxious, right?) fan bases in sports. That's the result of a great deal of success and an admittedly badass color scheme and logo. The Raiders aren't just easy to hate, they're difficult not to hate.
That leaves us with the question, "who do you hate losing to the most after the Raiders?" I expect a lot of you to name another AFC West rival, and if you do I'd also like to hear which non-AFC West team is next on your list, but for me the team I hate watching my Chargers lose to the most is the Pittsburgh Steelers.
The Pittsburgh Steelers, much like the Raiders, were really good for an extended period of time before I was born. They also play in a state with a miserable climate. As such, their fans (and there are a bunch of them) have spread out across the country and can be found in just about any sports bar you visit on a Sunday in football season. Also, they tend to be the variety of fan that likes to act as though they're somehow responsible for the success of the franchise they choose to root for. It's pretty terrible, and they should feel terrible for being that kind of person, but they don't. Their complete lack of shame over things they should be ashamed of only makes it worse. The fact that the Chargers never beat the Steelers also adds fuel to the fire.
Anyway, let us know in the comments who you hate losing to the most!