The Argentine is of the opinion that the two teams meet way too often, which in turn means they know each other so well that they cannot surprise each other anymore
The two teams played each other four times in the spring of 2011, twice in the Champions League, once in the league and faced each other in the Copa del Rey final.
Mascherano shared that he does not remember those clashes fondly as he believes they put too much strain on the players.
"Those four Clasicos will never be forgotten. It was terrible for what happened. We played too many times,” Mascherano told El Periodico.
The Argentine believes that the two teams know each other so well now that it is difficult to spot a new weakness or spring a surprise for the opposition.
"The more familiar you are, the worse it is - it is harder to find the weaknesses. It will be hard on Sunday."
The former Liverpool player also spoke of his transition from a midfielder to a center half and stressed how difficult it is to break into Barcelona's midfield.
"They were the best club in the world having won everything. I came here and finished my first season playing a Champions League final at Wembley against Manchester United. At center back!
"I am not Sergio Busquets, to play in the midfield for Barcelona is almost impossible. You need an almost perfect sense of positioning. For some games I can play there, but I always want to play."