Barcelona versus Real Madrid is one of the most intense football rivalries on the planet.
When the two Spanish giants do battle on the pitch, pretty much every country on Earth tunes in to watch the action unfold.
The hatred between the sides is real. It was probably never more apparent than when Barca fans threw a pig's head at Luis Figo after the Portuguese's controversial move to Real Madrid in 2000.
Very few players have crossed the divide, with Figo, Michael Laudrup and Luis Enrique three of the only big names to have done so.
It's simple, if you're a fan of the other, you never, ever praise your nemesis. Even some of the biggest names in sport take their pledge to one of the Spanish sides incredibly seriously.
UFC lightweight champion Khabib Nurmagomedov once refused to take a picture with a young Barcelona fan until he uttered the phrase: "Hala Madrid!"
The Russian is a true Madridista!
The Barcelona fan in question eventually gave in and fair play to him. Who would miss out on a photo opportunity with one of the biggest sporting star's on the planet over two words?
Especially when the guy making the demand is a person who beats up professional MMA fighters for fun...
But without that on-pitch rivalry between the two best players possibly to have ever graced the game, El Clasico has lost that edge which made it such a unique spectacle.
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