The World Anti-Doping Agency is urging soccer to conduct more blood doping tests and intelligence operations to unmask cheating players.
WADA Director General David Howman warned on Tuesday that "team sports players can go their entire career without being tested."
WADA President John Fahey added that "football is not testing enough for (blood-boosting) EPO ... we are encouraging them to do more."
Last week, Spain's anti-doping agency announced it was examining claims by a former president of Spanish team Real Sociedad that its players used performance-enhancing substances.
Fahey also urged soccer to "use intelligence" after highlighting its importance to building a case against Lance Armstrong.
Fahey says sport must be "alert to the increasingly sophisticated science available to athletes today and to the growing influence of the underworld."