Daryl Impey (Orica-GreenEDGE) says he is ‘extremely distressed’ after confirming he had failed a doping control test at the South African national time trial championships.

Impey, who became the first African to ever pull on the Tour de France yellow jersey 12 months ago, has been omitted from Orica-GreenEDGE’s nine-man squad this year.

And writing on his personal website, Impey confirmed that he had been informed of an adverse analytical finding for masking agent Probenecid following an in-competition test in February.

Though claiming in his statement that anti-doping tests two days later had yielded no adverse findings, the testing of his B-sample – conducted on June 27 – confirmed the failed test.

“I had no knowledge of Probenecid nor have I ever taken the substance knowingly in any manner,” he said. “I am committed to drug-free sport and fully intend to take all steps necessary to clear myself of any suspicion.

“The notification came as a complete shock to me just days before the start of the Tour de France, particularly since anti-doping tests conducted on me on February 8 and 9 2014 yielded no adverse results.

“I am extremely distressed by the finding, as I have always raced clean throughout my career. Every result that I have achieved to date has been as a result of hard work and dedication on my part.

“I notified my team immediately after being informed by Cycling South Africa of the adverse finding. I would like to thank them, my family and friends for their support during this difficult time.

“I remain confident that I will be vindicated and proved innocent of any wrongdoing.”

Orica-GreenEDGE confirmed in a separate statement they had been made aware of the failed test, and have provisionally suspended Impey until further notice.