Individuals & teams that always seem to let you down

Who are they in your experience?

We all seem to have individual players and teams in various sports who we try to avoid backing (or laying) for fear that they will let us down again, like they did before against all expectations.

In many cases, these teams or individuals don't actually perform any better/worse for us than any others over a long period. It just SEEMS that way - we tend to remember more easily the best and worst extremes and in the worst cases it can breed an irrational hatred for those concerned.

For me, in football terms, Fulham and Barnsley spring to mind as those who always seem to do the opposite to what I've backed (or layed). I find Fulham are especially difficult to predict when dabbling in the over 2.5 goals market.

In recent times, I've been on the wrong end of several Federer defeats. But when I tell myself that he is now over the hill and should thus be avoided, he keeps coming back to prove people wrong. Oh to have been 'on him' when he was on that great relentless run of success that spanned years.

How about you?