People protesting against the World Cup or in favour of more social spending could harm the country's chances of winning the tournament, Brazil manager Luiz Felipe Scolari said on Sunday.
Hundreds of thousands of Brazilians took to the streets during last year's Confederations Cup to protest World Cup spending and a lack of infrastructure investment.
Smaller scale protests are still occurring in the country, which will host the June 12-July 13 tournament for the first time since 1950.
Scolari said he was not against demonstrations but the World Cup was not the best time for his players to be confronted with any outside issues.
"I think protests can happen," Scolari said in an interview on Fantastico, a popular television show. "If they are normal, without smashing things up, then that is democracy.
"But I don't know if it's the right time.
"They are Brazil players and they have one mission. They can think, they can express themselves, they can say 'I want a better Brazil, too', but I don't want it to be something that causes problems in our environment."
When asked if protests could affect the players, Scolari replied: "It could, big time."
There is concern that protestors will try to disrupt some of the 64 World Cup matches after they marched towards the stadia used in last year's Confederations Cup.
They were often held back by riot police using dogs, percussion grenades and tear gas and police have undergone further training to make sure there is no repeat.
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