Russian sailor Pavel Sozykin will be able to compete at Rio 2016 after the World Sailing Federation reversed its decision to ban the 470 Class competitor.
World Sailing banned Sozykin in July following the findings of the McLaren report, which alleged there had been state-sponsored doping within Russia.
Sozykin was the only member of Russia's squad originally denied a place in Brazil, with the other six provisionally confirmed for the Games.
However, having received additional guidance from the International Olympic Committee (IOC), the decision has been overturned.
"Based upon the new guidance provided by the IOC, it was the unanimous decision of the participating World Sailing Board Members to declare Mr Sozykin eligible to compete in Rio 2016," a statement read.
"Mr Sozykin's entry for the Rio 2016 Olympic Games must still be confirmed by the IOC and the review panel established through the Court of Arbitration for Sport.
"The IOC provided the new guidance yesterday (2 August) in a circular letter to all summer International Federations. Specifically, with respect to the McLaren Independent Investigations Report commissioned by the World Anti-Doping Agency (WADA), the IOC has indicated that an athlete should not be considered as "implicated" if the McLaren list does not refer to a prohibited substance which would have given rise to an anti-doping rules violation.
"In the case of Mr Sozykin, though he was identified in the McLaren Report in connection with the Disappearing Positive Methodology, the report did not include specific information as to whether the positive test occurred in-competition or out-of-competition. Further, the substance for which he tested positive is not prohibited out-of-competition and, if the sample had been taken out-of-competition, would not have resulted in a sanction.
"The World Sailing Board of Directors also noted that Mr Sozykin has had at least two subsequent anti-doping tests with no adverse results."
World Sailing has warned Sozykin it will continue to monitor his situation and should he be found guilty of an anti-doping violation they could disqualify him from any results since October 2014, when his sample in question was taken.