RIO DE JANEIRO (AP) The first Olympics in Brazil are underway - aptly with soccer games in the sport's spiritual home and a win for the hosts.
In Rio de Janeiro's Olympic Stadium, the Brazilian women's team eased to a 3-0 victory at the start of its quest for a first Olympic gold.
It's an early sporting high for Brazil, where reservations about the cost of bringing the Olympics to South America for the first time have produced violent reactions.
As the Olympic torch relay reached Rio, there were fresh signs that strife could disrupt the games.
Police used tear gas to break up protests against salary delays for public workers. Other protesters are demanding improvements in education and healthcare, with some angered by the 39.1 billion Brazilian reals ($12 billion) - a mix of public and private money - being spent on building venues and infrastructure for the Olympics.
Brazil embarked on its Olympics bid at a time of prosperity in 2006, but the games are opening with the country in the grip of its worst recession in decades.
But there was a cause for celebrations on the football field as headers from Monica and Cristiane either side of Andressa Alves' 59th-minute strike secured Brazil's opening win over China.
The Olympic Stadium was fuller than earlier in the day when Sweden beat South Africa 1-0 in the other Group E game but the majority of seats did not appear to be filled.
The stadium is also known as Joao Havelange Stadium, named after the 100-year-old Brazilian who led soccer's governing body FIFA for 24 years. Havelange stepped down as honorary president of FIFA in 2013 to avoid possible suspension for taking kickbacks.
At the Mineirao Stadium in Belo Horizonte, site of Brazil's humiliating 7-1 loss to Germany in the World Cup semifinal two years ago, the U.S. women's team opened its bid for a fourth straight gold medal with a 2-0 win over New Zealand. Near the end of the game, local fans chanted ''Zika, Zika'' at American goalkeeper Hope Solo, who before coming to the Olympics upset some Brazilians by tweeting a photo of herself wearing a hat with mosquito netting in a reference to the virus.
In the final game of the day in Belo Horizonte, France cruised past Colombia 4-0 to take the group lead over the Americans.
The soccer in Sao Paulo saw a piece of Olympic history created by Canada. Janine Beckie took only 20 seconds to make a mark on her third Summer Games by scoring the fastest goal ever at the Olympics in a 2-0 win over Australia. It was nine seconds faster than Oribe Peralta's strike for Mexico in the men's gold medal match against Brazil four years ago in London.
Canada had to cope from the 19th minute with only 10 women after Shelina Zadorsky was sent off for dragging down Michelle Heyman on her way to goal. But Canada still prevented Australia from equalizing and captain Christine Sinclair added a second in the 78th.
In Sao Paulo, Melanie Behringer scored a pair of goals as three-time bronze medalist Germany routed newcomer Zimbabwe 6-1.
The men's soccer competition starts with eight games Thursday, with Brazil playing South Africa in the capital Brasilia.
AP Sports Writer Tales Azzoni contributed to this report from Belo Horizonte.