Christine Ohuruogu faces her day of judgement today after being provisionally suspended for missing three out-of-competition doping tests.
The 23-year-old Commonwealth 400 metres champion has to convince the three-man independent panel that she had good reasons for missing at least one of the tests at times when she had guaranteed her availability - or she faces a one year ban and exclusion from all future Olympics.
Marion Jones, America's multiple Olympic medallist, meanwhile faces a potential challenge to her clearance from doping charges after last week's test of her B sample for the banned blood-boosting substance EPO proved negative.
Dick Pound, chairman of the World Anti-Doping Agency, yesterday indicated his unease over the result, which contradicted the initial test on Jones' sample in June. Pound has refused to rule out the possibility of reversing the results if new evidence suggests there has been a mistake.
"It is always disturbing when the same sample is analysed on one occasion and you get a positive result and another and you get a negative,'' he told BBC Radio Five.
Jones' lawyer, Howard Jacobs, insisted that it was the initial "borderline'' A sample which should be investigated, adding: "He [Pound] should talk to a scientist before making such statements. I don't know if he is going to shop around until he gets the answer he wants but I hope not.''
The second day of the World Athletics finals in Stuttgart produced further disappointment for British athletes as Rebecca Lyne came only fifth in the 800m final - earning £2,700 - and Jo Pavey was seventh in the 3,000m.