Manchester City says defender Kolo Toure was suspended Thursday after failing a doping test.
City issued a statement Thursday saying "the FA has informed Kolo Toure that an 'A sample' provided by him has tested positive for a specified substance."
The club said Toure has been suspended from all matches "pending the outcome of the legal process."
The World Anti-Doping Agency defines a specified substance as one that is "more susceptible to a credible, non-doping explanation." Its punishment for such a positive test ranges from a warning to a two-year ban.
The 29-year-old Toure joined City from Arsenal in 2009. He was City's captain under former manager Mark Hughes but was replaced as captain this season by Carlos Tevez.
His brother Yaya Toure also plays for City.