British cyclist Lizzie Armitstead has won her appeal against a UK Anti-Doping suspension, freeing her up to compete at the Olympic Games in Rio de Janeiro.

The 27-year-old, who earned silver in the road race at London 2012, was charged for allegedly missing three drug tests during August and October 2015, as well as June this year.

Anti-Doping rules state that if an athlete fails three tests within 12 months, they could face a four-year suspension, but the Court of Arbitration for Sport has struck one of Armitstead's failures from her record.

It was found that the testing official was refused the cyclist's room number by reception after arriving at a hotel in Sweden, and phone calls to Armitstead were not picked up as the athlete was sleeping.

CAS has claimed that the decision to scrap one of the failed tests was 'unanimous'.

A statement released on behalf of Armitstead read: "The ruling relates to a UKAD anti-doping test which was asserted to have been attempted on Thursday 20 August, 2015, whilst Armitstead was staying at the team hotel, during the UCI Women's Road World Cup in Sweden."

Armitstead said: "I have always been and will always be a clean athlete and have been vocal in my anti-doping stance throughout my career. I am pleased CAS has accepted my position, having provided detailed information demonstrating the situation around my strikes.

"This issue was one of administration and was the result of Ukad not following proper procedure nor fully attempting to make contact with me despite clear details being provided under 'whereabouts'. I was tested in competition the day after this test, reinforcing my position that I do not cheat and had no intention of not being tested.

"I think that there should be clearer guidelines for those administrating tests and would like to work with UKAD going forward to explore how this can be better addressed in the future so no other athlete is put in this position."

The Olympic road race will be held this Sunday.