From Ben Johnson to Marion Jones, the world of sprinting has been blighted by numerous high-profile doping scandals.
Its reputation was further sullied following Sunday's startling revelations of positive tests returned by two of the four fastest men in history, Tyson Gay and Asafa Powell.
We look back at some of sprinting's most notorious drug cases:
At the Olympic Games in Seoul, Canadian star Ben Johnson tests positive for anabolic steroid stanozolol a few days after his victory in the 100m final, won in a world-record time of 9.79 seconds. It marked the first major doping scandal in Games history. Johnson received a two-year suspension before he was subsequently issued a lifetime ban after another positive test in 1993.
Barcelona Olympic 100m champion Linford Christie, who at 32 became the oldest man to win athletics' blue-riband event, was hit with a two-year suspension after testing positive for nandrolone.
Recently crowned 100m and 200m world champion Kelli White admits taking banned substances.
British sprinter Dwain Chambers, at the time co-holder of the European 100m record, receives a two-year ban for testing positive for designer steroid THG in the BALCO laboratory affair.
Greek sprinters Kostas Kenteris and Ekaterini Thanou are excluded on the eve of the Athens Games after being accused of faking a motorcycle crash to skip drugs testing.
American Tim Montgomery, a former 100m world-record holder after running 9.78sec in 2002, is banned for two years by the Court of Arbitration for Sport after he was implicated in the BALCO scandal.
Justin Gatlin, the defending 100m Olympic champion, is slapped with a four-year ban after testing positive for testosterone three weeks after equalling the world record (9.77sec at the time). Five years earlier, the American had returned a sample that tested positive for amphetamines.
Marion Jones admits to taking steroids from as early as 1999, an admission that costs her five medals (three gold, two bronze) from the 2000 Olympics. She also received a six-month prison sentence for perjury in 2008 for denying any role in the BALCO affair.
Jamaican Yohan Blake gets a three-month ban after a test comes back positive for the stimulant methylhexanamine. Two years later he becomes world champion in the 100m, benefitting from the disqualification of compatriot Usain Bolt in the final. He co-owns the second fastest time in history alongside Tyson Gay (9.69sec).
Jamaica's Olympic and world 100m champion Shelly-Ann Fraser receives a six-month suspension after testing positive for the painkiller oxycodone. She retains her Olympic crown two years later in London.
Steve Mullings of Jamaica is hit with a lifetime ban following a positive test for a masking product after having run a personal best 9.80sec. Mullings had already been sanctioned in 2004 after testing positive for testosterone.
Veronica Campbell-Brown, the reigning world champion and a two-time Olympic gold medallist in the 200m, is provisionally suspended following a positive test for a diuretic.
USA star Tyson Gay reveals he provided an out-of-competition sample in May that returned positive without specifying the banned substance in question.
A few hours later, Jamaica's Asafa Powell, the fourth quickest man in history over 100m, reveals he tested positive for oxilofrine, a stimulant similar to ephedrine. Both await the results of a B sample ahead of possible sanctions.