Two high-profile cases at the end of this year highlight the growing scrutiny over doping cheats in sports.
First America's former sprint king Tim Montgomerie was banned for two years for doping despite the fact that he had never tested positive.
The Court of Arbitration for Sport, who upheld the verdict by the US Anti-doping Agency earlier this month, based the ban on testimony from shamed runner Kelli White and evidence gathered in a criminal investigation of the California-based Bay Area Laboratory Co-Operative(BALCO).
World Anti-doping Agency (WADA) head Dick Pound has hailed the decision as a major breakthrough in the battle against doping.
"Finally a stake has been driven through the heart of the preposterous argument that you have to have a doping infraction by producing an analytical positive doping test," said Pound.
"It is a good warning. It means if you are going to do this drug stuff, you are at risk. It will be helpful as a deterrent," he added
In the second case, Argentine tennis player Mariano Puerta was banned for eight years, the longest ban in tennis history, after he failed a test for the banned stimulant etilefrine immediately after the French Open final, which he lost in four sets to Rafael Nadal.
The International Tennis Federation seems to have little sympathy in handing down the verdict to the 27-year-old for his second doping offense. Before the French Open final, he had served a nine-month ban after testing positive for clenbuterol during a tournament in Vina del Mar, Chile, in February 2003.
"Somebody who has tested positive twice in less than two years is someone who clearly doesn't think the rules apply to him," Pound said of the case.
"The testing regimes will get better over time and the deterrent effect of these kind of sanctions where positive cases are discovered will I hope persuade players who might otherwise consider using these drugs not to do so.
Another big name who made headlines was American Lance Armstrong, who French sports paper L'equipe alleged that six of Armstrong's frozen urine samples from the 199 Tour came back positive for endurance-boosting EPO.
Armstrong has been fighting vehemently against the allegations, but Pound had warned the American that WADA was continuing to build evidence against him.
"It (the case) is not going to go away. We're dealing with all the spins out there right now but behind scenes there are investigations quietly proceeding."
"There is no urgency because he is not going to be in another race but there are some explanations that are going to have to be given."
Armstrong is entitled to the presumption of innocence before WADA and International Cycling Union complete their own investigations but the way of testing doping samples kept from past years would force athletes to have a rethink of doping.
The International Olympic Committee (IOC) president Jacques Rogge had said that he wanted to extend to all sporting federations the system of keeping doping samples for eight years for possible retroactive sanctions.
Sports federations would feel the urgency in the fight against doping, in particular after baseball was excluded from the Olympic program in 2012.
Baseball and softball failed to win a majority of votes in the IOC Session in Singapore in July, becoming the first sports to be cut from the Games since polo in 1936.
One of the key reasons was the doping record in baseball, in particular in the United States where the image of the sport has been tarnished in the past year after a number of leading players were linked to steroid use.
There will be no exception to the winter sports, as the IOC has planned to perform 1,200 tests at next February's Turin Olympics, which is 45 percent more than the number at the last Winter Games in Salt Lake City in 2002.
"We remain with our zero tolerance policy, so that the fight against doping remains the very first priority of the International Olympic Committee," said Rogge.