Athletics chiefs have confirmed that they have appealed against the acquittal of Greek athletes Kostas Kenteris and Katerina Thanou.
Kenteris and Thanou were alleged to have missed three tests
The high-profile duo were cleared by Greek officials of avoiding a drugs test during last year's Olympic Games.
But the International Association of Athletics Federations (IAAF) was unhappy with the move and has appealed to the Court of Arbitration for Sport.
The IAAF is seeking minimum two-year bans for both athletes.
Kenteris and Thanou dramatically withdrew from last summer's Olympics in Athens after missing a drugs test at the Olympic Village on 12 August.
The pair then spent four days in a hospital, claiming they had been injured in a motorcycle crash.
It was the International Olympic Committee who demanded the IAAF investigate the affair.
Thanou and Kenteris still face a criminal trial later this year for allegedly avoiding the test and then faking a motorcycle accident.
Kenteris won the men's 200m at the Sydney Olympics in 2000 while Thanou won silver in the women's 100m.