Former Chelsea and Portugal midfielder Deco has had his positive test for a banned diuretic confirmed after his 'B' sample was returned on Friday.
The 35-year-old Fluminense player now faces an automatic 30-day ban, although he plans to fight against a suspension, claiming that the positive test is the result of a contaminated vitamin supplement.
Deco was tested after Fluminense's 2-0 win over Boavista on March 30. His sample contained traces of furosemide, a diuretic which can be used to mask other substances.
In a statement on their official website, Fluminense said that the player had hired his own lawyers to represent him in the case.