"The fact that the scientific hurdle has been overcome means this is a very, very good day for sport," says John Boultbee, director of the Australian Institute of Sport, which led the development of the blood test. "EPO has been the worst of the undetectable drugs that is prevalent in the sporting society. Now, those who cheat with EPO know that they should stop or not come to the Games, and those who don't cheat will know that we're much closer now to a level playing field."

The IOC has been under scrutiny and pressure on a variety of fronts since fall 1998, when the scandal concerning Salt Lake City's selection as the site of the 2002 Winter Games broke. Doping returned to the news in the USA recently with former U.S. Olympic Committee drug control director Wade Exum's allegations that, among other things, U.S. athletes won Olympic medals after testing positive for performance-enhancing substances at Olympic trials. (USOC officials have denied Exum's allegations.) In Australia, former Olympic discus thrower Werner Reiterer published a book in July alleging that drug abuse is rife among elite athletes in Australia and covertly sanctioned by a handful of Australian officials, prompting a probe there.

The IOC's plan is to begin random, unannounced testing Sept. 2 in Sydney, the day the Olympic village opens, and to continue testing until the end of the Games on Oct. 1. Medalists won't be automatically tested for EPO, as is the case with the Olympic drug testing already in place.