Mariya Savinova has lost her Olympic 800m title from London 2012 after being found guilty of doping.
The Russian has been banned until 2019 and had all her results nullified from July 2010 to August 2013.
It means Caster Semenya will be the new Olympic champion in that event from London. The South African was last at the bell in London and only sixth with 120m to go, but she finished strongly to finish runner-up and that effort has now proved worthwhile as she will claim the gold medal to go with the Olympic title she won in Rio last year.
Savinova also beat Jenny Meadows to bronze at the 2010 European Championships in Barcelona – and the Briton could now enjoy an upgrade. However Meadows was also a close second to Savinova at the 2010 World Indoor Championships in Doha but that race is earlier than the period during which Savinova’s race record will be annulled.
Savinova will also lose her 800m gold from the 2011 World Championships in Daegu (Semenya was again runner-up), although the Diamond League will struggle to recoup all the money she fraudulently made on the grand prix circuit.
A Court of Arbitration for Sport statement read: "On the basis of clear evidence, including the evidence derived from her biological passport (ABP), Mariya Savinova is found to have been engaged in using doping from 26 July 2010 (the eve of the European Championship in Barcelona) through to 19 August 2013 (the day after the World Championship in Moscow).
"As a consequence, a four-year period of ineligibility, beginning on 24 August 2015, has been imposed and all results achieved between 26 July 2010 and 19 August 2013, are disqualified and any prizes, medals, prize and appearance money forfeited."
Savinova, 31, has not raced since 2013 after being suspended during an investigation sparked by whistleblower Yuliya Stepanova.