Hosts Great Britain enjoyed a winning start to the London Olympics Wednesday as officials unveiled a new weapon in the fight against doping -- and revealed a string of new drugs bans.
Britain's women's footballers beat New Zealand 1-0 at Cardiff's Millennium Stadium as Olympic competition got under way, in bright sunshine, two days before the official opening ceremony.
Stephanie Houghton's free-kick after 64 minutes proved the clincher for the British team, who were playing their first ever Olympic women's football match.
In Glasgow, heavyweights the United States came from two goals down to beat France 4-2, while Japan's 'Nadeshiko', the reigning world champions, overcame Canada 2-1.
Brazil play Cameroon, Sweden face South Africa and Colombia take on North Korea later at the start of a 19-day festival of sport, years in the making and costing billions of dollars, which will be watched around the globe.
China, who topped the medals table at the 2008 Beijing Olympics, arrived at the athletes village as thousands of competitors, coaches, officials and media poured through London's Heathrow Airport and headed to Olympic Park.
"All athletes and teams are in good spirits and are performing their training every day as scheduled," said deputy chef de mission Xiao Tian.
"They're very eager to compete with athletes from other countries and delegations."
At the Games, Usain Bolt is hoping for a second successive sprint treble, Michael Phelps needs just three more swimming medals to become history's most decorated Olympian, and Roger Federer leads a galaxy of tennis stars.
Anti-doping officials said the London Olympics would be most stringently patrolled Games yet, boosted by a sophisticated new test for human growth hormone.
"It's a very significant step and it's a very helpful one," said World Anti-Doping Agency (WADA) Director General David Howman.
"Every step is significant if it ends up catching someone who has been cheating with impunity.
"Essentially it differentiates between the human growth hormone that is produced in the body naturally and that which has been introduced by artificial means."
Crucially, the new test had a detection window of "weeks rather than hours", Howman said.
Athletics' global governing body said a total of 10 competitors had been banned for doping, including six caught with its "biological passport" system and three after re-tests of samples taken at last year's world championships.
Morocco's Mariem Alaoui Selsouli, one of the favourites for the women's 1500m, was also banned after failing a test earlier this month.
Separately, Greek triple jumper Voula Papachristou was kicked out of the Olympics for a racist tweet which poked fun at Africans living in the country.
And "Slumdog Millionaire" director Danny Boyle was set to lead a team of 10,000 participants in the full dress rehearsal for Friday's hotly anticipated opening ceremony.
While details of the show -- which has much to live up to after Beijing's lavish opener -- are a closely guarded secret, it is expected to feature cows and sheep along with Sir Paul McCartney and David Beckham.