Pep Guardiola said he would not have played Sunday's LaLiga fixture against Las Palmas if he was still at Barcelona amid political tensions in Catalonia.
Barca preserved their 100 per cent start to the league season with a 3-0 win at Camp Nou, where no fans were present after violence marred the Catalan independence referendum.
The Barca board decided to play the game behind closed doors after their request to have the match postponed was rejected by LaLiga amid violent scenes during Catalonia's independence referendum, which was declared illegal by the nation's constitutional court.
"I would not have played the match," former Barca head coach Guardiola said in interviews with Catalunya Radio and RAC1 on Sunday.
"And if we did have to play it, then not behind closed doors."
"We don't want them to think that we dislike Spain," he added. "Spain is an incredible country, with its literature, sport and cities. But there is a need to understand that there is a population which wishes to decide its own future."
It was a day of violence as riot police clashed with protesters, who went to the polls in the Catalan region.
Footage emerged of law enforcement officers using batons and rubber bullets on the crowd, while voters were forcibly removed from some polling stations.
"Spain will try to cover up the reality, but the rest of the world's media will show it," Manchester City manager Guardiola said.
"I read in El Pais that they were saying it was the police officers who were injured. Injured by what? By votes?
"It has been the opposite as they have injured people with rubber bullets, which are illegal in Catalonia. They broke one woman's fingers. There are some images from today that are irrefutable.
"The prime minister must answer the questions, as he remains the prime minister of all Spaniards.
"Why don't we be more like the British, who have been democratic for many more centuries than us? On top of it all, we don't even know if Catalonia does or does not want to be independent."