Red Bull Salzburg players Mohamed Camara and Sékou Koïta were both suspended by UEFA for three months on Thursday for doping use.
The two took a positive test in November last year after returning from an international match with Mali.
It is unknown which banned substance is involved, but traces of a substance in the blood of both midfielder Camara and attacker Koita were found that is used for a medicine to fight altitude sickness.
Both players stated that they were given the drug by the medical staff of the Malian national team for the away game against Namibia (1-2 win).
'De Adelaars' flew for the qualifying match for the Africa Cup from 350 meters in Bamako to 1,700 meters in Windhoek.
Koïta made it 0-1 in that match.
Three days later, Camara and Koïta both came into action for ninety minutes in the Champions League match with Bayern Munich (3-1 loss).
Later they also played against Lokomotiv Moscow and Atlético Madrid.
Salzburg finished third in the group and therefore continued in the Europa League.
The suspension of Camara and Koïta is effective immediately and applies to all matches at both club and international level.
This means that the pair cannot take action on Thursday-evening in the first leg of Red Bull Salzburg against Villarreal in the second round of the Europa League.
The 21-year-old Koïta is on track this season with fourteen goals in sixteen league matches.
In a European context, the striker did not score this year.
Camara, also 21, has not scored a single goal for his club this season.