DYNAMOS and Zimbabwe midfielder Devon Chafa has failed a routine Fifa doping test conducted during the 2014 World Cup qualifier against Egypt in July.
The player says the banned substance probably came from medication he was taking, and his doctors - through Zifa, have sent samples to Fifa.
Professional sportsmen should clear all medication they are taking with their teams' medical staff, but according to Zifa, no such clearance from the national team's medical staff was sought by Chafa.
Zifa communications manager Xolisani Gwesela said: "Fifa wrote to Zifa on July 17, 2013, to the effect that during a doping procedure, they found a prohibited substance. This substance was linked to Devon Chafa.
"Fifa then requested our team doctor, Nicholas Munyonga, to look at the letter and provide Fifa with the player's proof that he was taking medication linked to that substance.
"Munyonga communicated that the player and his family's medical practitioner had confirmed that the player took the substance for medical reasons. So we are awaiting communication from Fifa."
The substance has been identified as prednisone. It can be found in many different treatments including medication for asthma, allergic disorders, severe tuberculosis and as part of a drug regimen to prevent rejection post-organ transplant.
Prednisone has also been used in the treatment of migraine headaches and is important in the treatment of acute leukemia and other hormone-sensitive tumors, in combination with other anticancer drugs.
If found guilty, Chafa could face a lengthy spell on the sidelines.