They might hate a coach or a player. Fans might hate how the last game went. They might also hate how a Merengue fan behaves.
But it's undeniable that hate is strong amidst Madrid and Barcelona and there are some very strong reasons for it.
I'm sure you've all heard this one before:
"X" is the best because he plays for Madrid.
Sometimes "X" isn't even in the contention for best player, but just because he's dressing in white he's instantly good.
This is especially noticeable in video games, where an average player in Madrid gets an instant stat boost just because he's there.
Another very valid reason to hate Madrid is that even though Barcelona are in their historic high-point; who's Spain's coach?
That's right, a Madrid coach in the form of Vicente del Bosque.
And who's the player that can't miss a single game?
Real Madrid's Xabi Alonso.
I know Spain won the World Cup. But they won it ugly thanks to Xabi and Vicente.
Without them, they would have steamrolled over everybody at South Africa.
Let's get something straight first: Luis Figo is no saint.
But the fact Madrid splashed loads of money certainly played its part too.
And it's not nice when someone leaves because he's getting paid more.
Speaking of money, here's the man responsible for Madrid's Galactico scheme: Florentino Pérez.
And what that means is putting together the power, money and politics of one of the world's top clubs and using that to get results on and off the pitch.
And if money and power corrupt people, Florentino is one of the most corrupt men around.
There's a word in Spanish that describes Madrid's traditional historic playing style as "pegada."
In English, what that means is that they score in the few chances they have.
And call me silly, but last time I checked, when you create few chances and depend on a star making a big play the whole game, you're not that far away from the playing style adopted by teams contending for promotion.
Pepe, Di María, Sergio Ramos, Arbeloa and Marcelo.
You'll have a tough time finding three players in the same team that are as dirty and unpleasant as these three.
And before them we had Gravesen, Guti, Emerson, Pablo García, Helguera, Míchel Salgado, Roberto Carlos, Fernando Hierro and Manolo Sanchís.
I could go on, but I think you get the picture.
One of the things I hate about Madrid is the support they get from the press.
And while you could argue that it's expected and that it doesn't play a big part, there is one thing they can do: put pressure into rivals and match officials.
Case in point: let's imagine you're a referee. Two minutes and there's a potential penalty against Madrid. What do you do?
a) Point to the spot and call it, while risking being on the cover of MARCA and receiving insults by the bucket-load the next day.
b) Pretend nothing happened. And then live in peace and without insults for the next week.
If you need explanations on this one, you'll never ever be an Antimadridista.
I've already explained how the press can (and does) play into official's calls for Madrid.
And yet, they take it a step further.
The call it "Villarato" and what that means is that Barcelona has a preferential treatment by the refs because of Angel Villar.
How? Never truly explained, yet it's a recurrent subject among Madridistas and their press week in and week out.
They've even added perks inside the UEFA, just for kicks.
All of this from a club that has always benefited from official's calls historically.
And when everything else fails a Madrid fan will go for this: "We've won nine Champions Leagues."
You know you've won against them when you hear something among that line.
Just be cool and try not to mention that they've only won three in the "modern" era when the final isn't played against that day's equivalent of today's Viktoria Plzen.
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