Former Chelsea, Barcelona and Porto midfielder Deco was on Tuesday cleared of doping and had a one year ban lifted by the Court of Arbitration for Sport (CAS).
Deco's decorated career ended under a cloud last September when he was found guilty of taking a banned diuretic by a laboratory in Rio de Janeiro.
The Rio lab detected the prohibited substance in a sample Deco had provided after playing for Fluminense in the Brazilian league on March 30, 2013.
But CAS, upholding the player's appeal, ruled that Deco was completely innocent of the charge, claiming there were major doubts as to the validity of the Brazilian control.
CAS noted that the testing centre in question had since been stripped of its World Anti-Doping Agency status.
A fresh test was ordered by world football's governing body FIFA by the official anti-doping laboratory in Lausanne which detected nothing untoward with the sample.
"No Prohibited Substance(s) or Metabolite(s) or Marker(s) of a Prohibited Method(s) on the test menu were detected..." the Lausanne experts informed CAS.
Deco won the Champions League with Porto in 2004 and again with Barcelona two years later.
He earned 75 caps for Portugal, and won the Premier League title with Chelsea in 2010, and the FA Cup twice.