Protesters tried to pass a police blockage outside Rio de Janeiro's Maracana stadium where Mexico were playing Italy in the tournament, a run-through event for next year's World Cup finals.
Police were filmed firing tear gas and rubber bullets at the crowd estimated by local media at around 600 people.
The protests are ostensibly against the costs of the World Cup but people are also angry in Rio about a local issue surrounding the cost of public transport. There were demonstrations around the country last week against public transport costs.
Protests also marred the opening day of the tournament on Saturday when around 500 protesters were tear-gassed by police in Brasilia where the hosts were playing Japan.
They have added to a sense of growing unrest in Brazil at a time when inflation, crime and the popularity of President Dilma Rousseff, who was at Saturday's game, have all taken a turn for the worse.
The Confederations Cup, an eight-team toournament, is considered a warm-up event for next year's World Cup.
Preparations for both events have been plagued by delays and cost-overruns and there are worries that stadiums in cities such as Brasilia, Cuiaba and Manaus, which do not have top-flight football teams, will become white elephants.