A tearful Gerard Pique described Barcelona's victory over Las Palmas which was played behind closed doors after violence marred Sunday's Catalan independence referendum as his "worst experience as a professional".

Barcelona made it seven wins from as many LaLiga matches with a 3-0 triumph at an empty Camp Nou, where the Barca board decided to play the fixture without fans after their request to have the match postponed was rejected by LaLiga.

Barca's appeal for postponement came amid violent scenes during Catalonia's independence referendum, which was declared illegal by the nation's constitutional court.

Speaking about the match and Sunday's events, outspoken Barca star and Spain international Pique told reporters: "It was a really difficult game to play. It was my worst experience as a professional.

"We all gave our opinions [in the dressing room], there were pros and cons for playing, but in the end, we decided to play.

"I understand that there are supporters who do not understand that decision."

Lionel Messi scored a second-half brace for Barca, while Sergio Busquets was also on target for the LaLiga leaders, who preserved their 100 per cent record.

Pique has been heavily criticised for encouraging people to vote in the referendum amid question marks over his future in the Spain team.

The 30-year-old – who did vote and has been the target of boos by Spain fans across the country – added: "If anyone believes I am a problem for the federation, I will step aside from the national team before the World Cup.

"Going with the national team is not a competition in patriotism, it's about trying to play the best you possibly can."