The Athletics Integrity Unit has confirmed former Olympic 1500m champion Asbel Kiprop has tested positive for the banned blood-boosting agent EPO and rejected a number of allegations the Kenyan made against officials.
Kiprop released a lengthy statement on Thursday claiming his doping sample might have been tampered with by testers who not only tipped him off about their visit in November last year but also took a payment from him.
The AIU, an independent body that manages all doping-related matters for athletics, conceded on Friday he had been given advanced notice but that it was satisfied there had been no interference with his sample.
"In the course of these proceedings, Mr Kiprop has made a number of public allegations in relation to the sample collection process," read a statement.
"These allegations have been investigated by the AIU. The AIU is satisfied that there has been no mix up or tampering with the sample."
Kiprop's case is now with an International Association of Athletics Federations (IAAF) disciplinary tribunal and the 28-year-old faces a ban of four years from the sport if found guilty of doping.
Among the more claims made by Kiprop, a senior police officer, was that he paid the testers an unspecified amount of money and did not consider it untoward.
"I did not at the time expect that the request for the money had anything to do with the sample," Kiprop said in the statement.
"At that time I did not see the money as inducement or bribe for anything. I gave it in good faith thinking they may have some need known to them.
"In retrospect, I now clearly see the money as having a relation with the sample collected on that date, and even the irregular advance notice I was given."