Liverpool defender Mamadou Sakho has been officially suspended after UEFA opened disciplinary proceedings against him following an anti-doping violation.
Sakho, 26, was stood down from first-team duty by Liverpool on Saturday after discussion between the club's owners Fenway Sports Group, manager Jurgen Klopp and the player himself.
Now UEFA has officially suspended the France international for 30 days pending the results of a full investigation.
PA Sport reported that the alleged offence relates to the Reds' Europa League second-leg tie at Manchester United, and French station RMC says it concerns a "fat-burning" substance.
A UEFA statement said: "Disciplinary proceedings have been instigated against Liverpool FC player Mamadou Sakho, following the UEFA Europa League round of 16 second-leg match between Manchester United FC and Liverpool FC (1-1), played on 17 March.
"The proceedings relate to a violation of the UEFA Anti-Doping Regulations, after the player failed a doping test at the above-mentioned match.
"The player did not request the analysis of the B sample. UEFA has now suspended the player provisionally for 30 days until a final decision is taken by the UEFA Control, Ethics and Disciplinary Body.
"The date of the disciplinary hearing will be announced at a later stage."