#1 Real Madrid 2-6 Barcelona, 2nd May 2009
Before this encounter, neither team had scored more than five goals against their rivals away from home. However, when Barcelona came to the Santiago Bernabeu during the end of the 2008/09 season, they were on course for a historic treble and were playing some of the best football the world has ever seen.
The result? The Catalan club smashed six past Real Madrid at their home ground, as the fans witnessed something unprecedented.
There is perhaps no Pep Guardiola team which played the level of football that this Barcelona team played in 2009. Real Madrid did not have Ronaldo with them at the time, but the squad was still one of the best in the world and they were outclassed by their rivals.
Lionel Messi and Thierry Henry hit twice each with Xavi Hernandez racking in a record four assists in a single game. The Los Blancos could do nothing but watch as Barca dominated possession and created more chances than they ever had in the El Clasico.
It was a masterclass from the world's best team and if there is one particular game where the Catalan club hit their peak under Pep, this was it. A mesmerising and dominant display which humbled the Madrid team in front of their support.