Amid reports of all eight British riders dropping out of Sunday's final day of the men's road race at the World Championships in Italy, it emerged that Team Sky rider Jonathan Tiernan-Locke has been asked by the International Cycling Union (UCI) to explain discrepancies in his blood values registered in September 2012.
He dropped out of the men's World Championships upon receiving the letter.
Should he fail to explain the irregularities, he could face a possible suspension or potentially lose his place on the number one team who have a 'zero tolerance' policy to doping.
Tiernan-Locke was riding for Endura at the time, and they have today defended the 2012 Tour of Britain winner with a statement.
It read: "At this early stage, without detailed information, it would be inappropriate to speculate on the reasons for inconsistencies in JTL's biological passport data, although it is known that there are many possible legitimate causes, including fatigue and ill health, both of which we understand JTL has suffered from in the last year.
"A process, that ought to have remained confidential, is under way and we obviously hope that JTL is able to provide information that is acceptable to the UCI for their enquiry in order for him to clear his name."
Performance director of British Cycling and Team Sky coach Sir David John "Dave" Brailsford has also defended Tiernan-Locke.
He told Sky Sports: "He hasn’t failed anything yet or there’s nothing where you would say absolutely categorically, this is something which needs to be addressed.
"It appears there’s an anomaly which needs to be looked at and explained. This isn’t the first time that this has occurred. We’ve got to allow them to carry on with the process, get both sides of their appropriate roles done, try to establish the truth – which is the important thing. Once we have the truth, we can all deal with that and go from there."
Brian Smith, who was Endura Racing’s general manager, told Cyclingnews: "I can put my hand up though and say 100 per cent that I don’t think he was doping at Endura Racing. There was no suspicion, no nothing."
Tiernan-Locke tweeted on Sunday following his departure from the men's road race saying: "Was sorry I had to withdraw from the worlds line-up, just don’t have the form to help the lads there."
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