The likes of Arsenal and Chelsea have been named in a report claiming widespread doping across British sport, including in the Premier League.
The Sunday Times reports that they have spoken to a British doctor who claims to have doped 150 sports stars, including a number of footballers from England's top flight.
The report goes on to mention Arsenal and Chelsea, in addition to current Premier League leaders Leicester City and Championship outfit Birmingham City.
It is not yet clear whether any players in question from the named clubs are still playing or not, nor whether the claims from the doctor are indeed true.
The report also says that the doctor has doped "an England cricketer, British Tour de France cyclists, a boxing champion and tennis players".
Doping in sport has been a hot topic in recent months, with athletics being rocked by a scandal involving Russia and five-time Grand Slam tennis champion Maria Sharapova being found to have taken a banned substance last month.