The biggest game of the La Liga season so far is shrouded in political tension as Barcelona visit Atletico Madrid on Saturday in their first trip to the Spanish capital since a Catalan independence referendum marred by violence.

Barca played their last match behind closed doors as the 1 October referendum, deemed illegal by the Spanish government, took place amid chaotic scenes as police seized ballot papers and clashed with voters, leaving 92 injured, among nearly 900 who sought medical attention.

"It was one of the worst moments we've experienced," Barca captain Andres Iniesta told Catalunya radio this week. "It was a bit surreal."

Iniesta, 33, signed a first ever "contract for life" at Barca last week, a day after calling on both sides of the political spectrum to negotiate.

However, deep divisions remain despite Catalonia president Carles Puigdemont's decision to suspend the effects of a unilateral declaration of independence on Tuesday.