Brazilian police mounted a huge operation at the Maracana on Wednesday night for Spain's clash against Tahiti, with 1,500 armed police drafted in to protect the stadium.
FIFA and the organisers of the Confederations Cup have said there are no plans to make any changes to the tournament schedule despite the protests.
Demonstrators are voicing their disapproval at the quality of public services, corruption and the high cost of staging next year's World Cup finals.
Protests are taking place throughout the country with an estimated one million people taking to the streets in more than 80 Brazilian cities.
Around 300,000 protesters poured into the central area of Rio with running clashes played out between police and groups of mainly young men in the early hours of Friday morning.
At least 40 people were injured in the clashes as police used tear gas and pepper spray to dispel the crowds.