The player in question, Frenchman Mamadou Sakho, was playing for Liverpool in 2016 when it was announced that he was being investigated for breaching anti-doping rules. He was subsequently found to have tested positive for higenamine, which is a fat-burning substance. UEFA banned him from all European football for a month, and FIFA subsequently expanded his suspension to include the worldwide game.
However, it was then transpired that the substance was not on WADAs proscribed list at all and even WADAs own laboratories were unsure as to how it should be classified. His ban was lifted and UEFA subsequently dismissed the case against him.
Although he was able to resume his career, he missed the chance to play in the Europa League Cup Final that year for his club. Sakho also alleges that it cost him a place in the France squad for the European Championships that year.
However, despite being cleared by UEFA, WADA continued to maintain his guilt and published statements revealing details of the case against him.
When the allegations against him were widely circulated in tabloid newspapers, Sakho sued WADA for defamation of character, and, more than four years after the incident, he has been completely vindicated.
WADA has issued a craven apology and has admitted that it should not have made the false statements about the footballer. They have also had to pay him significant damages in recompense for the harm that they have caused to his reputation and good name.
Sakho moved to Crystal Palace in 2017, the club that he still plays for, but his international career has never really recovered after the incident, and he last played for France two years ago.