A new test for human growth hormone, one of the most difficult banned substances to detect, is to be used at the London 2012 Olympics.
David Howman, the director general of the World Anti-Doping Agency (WADA), said the new test would work alongside existing detection methods for the substance.
Howman also ruled out the possibility of the lifetime Olympics ban for first-time drugs cheats ever being allowed.
HGH has been difficult to detect in the past because it is naturally occurring substance, but new methods have now come on stream.
Howman told a news conference at London's Olympic Park: "It is in place. The market test which is a new test for human growth hormone is in place and can be utilised by the laboratory during the Games.
"There is nothing else to add to that except the other test for human growth hormone will be used as well, so they are complementary, not separate."
