What's it like to referee a Clasico? EXCLUSIVE: "It is a game that can take more away than it gives you"

Gab Marcotti ponders who will fill the void of Cristiano Ronaldo and Lionel Messi and emerge as their side's hero on Sunday. Ramón Calderón spoke at a charity event ahead of the first Clasico without Cristiano Ronaldo and explained why he believes Madrid should not have sold him. Sunday's Clásico will be first one without Lionel Messi and Cristiano Ronaldo since December 2007. Here's some other big events from that year. Sunday's Clásico will be first one without Lionel Messi and Cristiano Ronaldo since December 2007. Here's some other big events from that year. La Liga's Clasico is the most watched domestic club game on the planet and nobody at the Camp Nou on Sunday will be more alone, in the unforgiving spotlight, than the referee. Clasico officials must be prepared to take monumental flak before, during and after the 90 minutes, receiving it from players, coaches, fans and pundits leaning towards either Real Madrid and Barcelona, and while trying to make split-second decisions that potentially have long-lasting consequences. Few referees know more...