Sevilla's Samir Nasri faces the prospect of being banned from football for up to four years with the World Anti-Doping Agency investigating his actions.
The Independent understands WADA are treating the case with 'the upmost urgency' after the midfielder, on loan from Manchester City, was found to have visited the Los Angeles intravenous therapy clinic 'Drip Doctors' last month.
The Spanish Agency for Health Protection in Sport (AEPSAD) – who covers anti-doping in the country – confirmed last month that the Frenchman is now under investigation (http://www.football-espana.net/62235/nasri-under-investigation).
Intravenous therapy is banned by WADA unless it is administered under quantities of 50 mililitres per six-hour period, although the 'Drip Doctors' clinic suggests their treatment is 100 militres in this time period.
“Whilst WADA does not yet have the full details and facts [regarding the situation], we are aware of this matter and expect the relevant anti-doping organization to investigate further,” said the organisation’s spokesman Ben Nichols.
“As with all anti-doping matters, we will be monitoring the work conducted by the applicable anti-doping organization.
“It is important that information is provided to and gathered by the investigating anti-doping organization as quickly as possible and in as much detail as possible, because the longer the period between the incident and the investigation, the greater the risk that certain evidence may no longer exist.
“Anti-doping organizations are required to come to a decision efficiently and without undue delay as to whether the proceedings should be brought against the athlete or other person."
The French midfielder is free to play for Los Rojiblancos in the meantime and he featured against Real Madrid in Wednesday's Copa Del Rey defeat, but a 'swift conclusion' is expected.