Rio de Janeiro - The first sporting action of the 2016 Olympics started in a virtually empty stadium on Wednesday as the Russian doping scandal rumbled on.
With the formal opening ceremony at the Maracana stadium just two days away, the women's football tournament started with a game between Sweden and South Africa.
There were just a few hundred spectators in the 60,000 Rio Olympic Stadium for the kickoff of the first of six games taking place across the country.
There should be a bigger crowd when hosts Brazil, led by Marta, make their bow against China at the same venue later in the day.
But tickets are available for many top Olympic attractions, including blue riband athletics races.
The women's football tournament launches what Brazilian fans hope will be a golden campaign for their men's and women's teams, who have never won an Olympic title.
"Although people say we don't have to go and win the gold, for me, as someone who has played at other Olympics, won two silvers and come close to the gold, I think we are obliged to win it," said Brazil striker Cristiane.
The first matches of the men's tournament will take place on Thursday, with Brazilian superstar Neymar spearheading the host nation's quest for a first ever Olympic gold medal -- the only international title every to elude the five-time World Cup winners.
The advent of the first sport of the Games will come as a welcome diversion for Olympic chiefs who have been mired in the fallout from the drugs scandal involving Russia.
International Olympic Committee (IOC) president Thomas Bach on Tuesday called for wide-ranging reforms of the World Anti-Doping Agency while the Court of Arbitration for Sport (CAS) rejected appeals by 17 Russian rowers against their exclusion from the Games.
With appeals involving a dozen other Russian swimmers, wrestlers and weightlifters still to be decided, the row over state-run doping blamed on the Russian government threatened to overshadow Friday's opening ceremony.
The IOC chief said the Russia scandal, which he has described as "contemptuous," had exposed deficiencies in WADA.
"Recent developments have shown that we need a full review of the WADA anti-doping system," he told an IOC session that continued Wednesday.
Late on Tuesday, Brazilian police used tear gas against demonstrators trying to obstruct the tour of the Olympic flame in a Rio de Janeiro suburb.
Ensuring security at the games has been an oing headache for organizers in a region which has witnessed a 17 percent spike in murders in the first half of 2016, according to official figures.
Chinese athletes and officials say they have been affected by several cases of crime since arriving in Brazil for the Games.
Among the latest to register a complaint was Chinese hurdler Shi Dongpeng, who was quoted by state media as saying that his personal computer was stolen on arrival.
Chinese athletes are among a range of athletes from different nations who have complained about conditions in the Olympic village.
Table tennis star Fan Zhendong showed pictures on the Weibo social media service of himself and teammate Zhang Jike fixing a broken shower curtain rail.
Australia's NBA basketball star Andrew Bogut made a series of posts on Twitter under the sarcastic hashtag #IOCLuxuryLodging documenting his various gripes about accommodation in the athletes' village.
Elsewhere, US Olympic officials confirmed that swimming superstar Michael Phelps would carry his country's flag into Friday's opening ceremony at the Maracana Stadium.
Phelps, the most decorated Olympian of all time with 22 medals including 18 golds, was chosen for the honor following a vote of Team USA members.
"I'm honored to be chosen, proud to represent the US, and humbled by the significance of carrying the flag and all it stands for," said Phelps, who will be swimming in his fifth Olympics.
Olympic fencing champion Lei Sheng will carry China's flag at the ceremony, becoming the first non-basketball player to get the honour since 1984.