Champion jockey Oisin Murphy has tested positive for cocaine and says he will “fight to clear my name”.
The 25-year-old Irishman denies taking the drug and says he is awaiting the result of a B sample following the test in France in July.
Murphy, who is number one jockey for Qatar Racing and on course to retain his championship, faces a six-month ban if he is found to have taken the drug.
He said subsequent hair tests have found no trace of the substance.
“I have never taken cocaine in my life and I will do everything that I can to prove that I have not taken cocaine,” he said.
“I want to thank those who are supporting me and in the meantime I want to keep riding winners and focus on my career.”
The jockey enjoyed a landmark success in June when winning the 2,000 Guineas at Newmarket aboard Kameko, trained by Andrew Balding.
He returned the positive test in a urine sample at Chantilly Racecourse on 19 July but has been allowed to continue riding while further investigations take place.
After being informed on 19 August by France Galop that his A sample had metabolites of cocaine, he organised for an independent laboratory to undertake hair tests, which were negative.
Murphy, who is due to have four rides at Chelmsford’s evening meeting on Thursday, leads the 2020 Flat Jockeys Championship with 111 winners - 13 ahead of nearest rival William Buick.