Dwain Chambers has been banned for two years by UK Athletics after he was found guilty of failing a drugs test.
Chambers failed an out of competition test for the banned steroid THG (tetrahydrogestrinone) and now faces two years out of the sport, but does have 60 days to appeal.
Chambers, the European 100 metres champion, failed the test on 1 August 2003 and has been banned after being found guilty by a UK Athletics disciplinary hearing on 19 February.
Chambers, who is 25, had been one of Britain's brightest hopes of a medal in the Olympic Games this autumn but he will now be absent in Athens as the guilty verdict carries with it a life ban from the Olympics.
An independent disciplinary committee, chaired by Charles Flint QC, has decided Chambers committed a doping offence after an out-of-competition test revealed THG (tetrahydrogestrinone), a substance related to the prohibited steroid gestrinone.
The International Association of Athletics Federations' doping rules state that Chambers must be banned for two years, a punishment which is back-dated to November 7, 2003.
The UK Athletics chief executive David Moorcroft said: "UK Athletics are proud of the fact that we conduct a full programme of in- and out-of-competition testing alongside targeted testing to ensure we do all we can to protect those athletes who compete fairly.
"We are mindful of the fact that this may lead to adverse findings and that publicity resulting from a positive finding can hurt the sport, but we feel this is a price worth paying to keep the sport clean.
"Athletics is one of only five sports in the UK that conduct a completely without warning full out-of-competition testing programme alongside in-competition testing.
"UK Athletics are also determined that any positive results from tests are dealt with fairly, independently and by appropriately qualified people.
"UK Athletics also actively promote anti-doping education to athletes, coaches, parents and other parties."Reuse content