Real went into the game at the Santiago Bernabeu with a mammoth 15-point advantage over their fierce rivals.
They would have been very confident of extending that gap even further.
But it all went wrong for Los Blancos as Barca dominated from start to finish.
Pierre-Emerick Aubameyang (2), Ronald Araujo and Ferran Torres were on the scoresheet in a convincing 4-0 victory for the Catalan giants.
There was a big moment in the first half when Vinicius Jr was denied a penalty.
With the scoreline 1-0 to Barcelona, Vinicius took a tumble inside the box and was convinced that he should have been given a spot-kick.
Tensions escalated as Vinicius clashed with a number of Barca players.
Moments later, Barca were given a corner and Araujo found the net to double his side’s lead.
A fascinating video, posted by El Dia Despues, has now emerged showing the interactions between both sets of players before the Uruguayan’s goal.
View it below…
29 seconds into the video, Vinicius goes down inside the box.
Marc-André ter Stegen immediately wags his fingers and says ‘no’ to the referee, before confronting Vinicius and saying he ‘dived’.
Vinicius has words with Gerard Pique before walking away saying ‘ok’.
Eder Militao then has words with the referee, who replies that Vinicius dived.
Barcelona are then given a corner and Vinicius continues his protests.
Militao, distracted by Vinicius’ complaints, shouts his name to get his attention.
Just as Militao shouts his countryman’s name, he forgets to mark Aruajo. The corner is swung in and Araujo beats Militao to the ball and heads home.
Football fans are enjoying the video and you can view some reaction below…
Militao lost concentration for a split-second and he was punished.
Despite the heavy defeat, Real are still in pole position to add another La Liga title to their trophy cabinet.
They currently enjoy a nine-point advantage over second placed Sevilla, with Barcelona a further three points back.
It will take a monumental collapse to prevent Real becoming Spanish champions for the 35th time.
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