British sprinter Nigel Levine has failed a drugs test.
Levine, 28, is alleged to have tested positive for the banned asthma drug clenbuterol and the Daily Mail reports he is waiting for his B sample result.
The European indoor gold medallist broke his pelvis in a motorbike crash in Spain in January - the accident also involved fellow Briton James Ellington.
Levine has returned to training but has not competed since and in April he told BBC Sport he was coping "pretty well".
Clenbuterol is on the World Anti-Doping Agency's prohibited list because it is deemed a performance-enhancing drug and can induce weight-loss.
Levine is no longer a client of Linford Christie's management consultancy Nuff Respect.
Ellington, 31, also broke his pelvis, as well fracturing his leg in two places, when the pair were hit by a car travelling towards them.