Calls for an independent global drug-testing agency are growing as it becomes clear many nations' procedures fall well below expected standards.
China's anti-doping head has said he was "shocked" after an anti-doping agency alleged the country produces large amounts of illegal substances.
Proteas' Rory Kleinveldt has failed a doping test by the South African Institute for Drug-Free Sport, testing positive for a "specified substance".
Alberto Contador is due to fight against an appeal to impose a doping ban on him which could strip him of his 2010 Tour de France title.
South Africa and the United States are among at least five countries that filed initial paperwork required ahead of any potential 2020 Olympic bids.
Springboks Chiliboy Ralepelle and Bjorn Basson will have to wait before hearing whether they will escape a ban for taking a banned substance.
The ability of only select laboratories to detect the small amount of clenbuterol in Contador's samples was not sufficient reason to clear the rider.
A French judge has issued an arrest warrant against American cyclist Floyd Landis for his suspected hacking into an anti-doping laboratory computer.
After his nightmare 2009 season, French tennis player Richard Gasquet insists he now wants to turn the page and get back to winning titles.
Gymnastics, wrestling and volleyball were among five Olympic sports cited by Wada for failing to implement out-of-competition testing programmes.
The most lavish Olympic Games of the modern era will get under way on Friday in the spectacular Bird's Nest stadium, with more than 80 heads of state.
World number one Tiger Woods and second-ranked Phil Mickelson applaud the new PGA Tour drug-test plan set to begin on July 1, even though it means careful monitoring when playing abroad. Mickelson said he sees no doping problem in golf but wants the anti-doping programme to ensure credibility with golf's audience.
Reversing years of denials, United States track superstar Marion Jones pleaded guilty on Friday to lying to federal investigators and admitted using steroids, which could cost her the five medals she won in the 2000 Olympics. In a sober court hearing and a tear-filled appearance before reporters, Jones (31) admitted using performance-enhancing drugs.
Suddenly there seem to be as many policemen involved in tennis as there are players. Gone are the days when a London bobby, with minimum fuss and barely a whiff of publicity, would quietly lead away an offending clergyman from the packed aisles of the outside courts at Wimbledon for having something less than pure intentions towards certain members of the watching flock.