A British doctor has claimed he helped doped 150 "stars" including premier league footballers, an England cricketer and tennis players.
Dr Mark Bonar made the allegations in meetings with undercover reporters, according to theSunday Times.
The paper said it had not been able to substantiate the claims elsewhere but Britain's culture secretary John Whittingdale has already ordered an inquiry into the UK Anti-Doping watchdog. The agency was given evidence about the doctor's doping activities two years ago but did not take any action, it was alleged.
The report stated Dr Bonar had treated more than 150 sports people from the UK and abroad with banned substances including erythropoietin (EPO), steroids and human growth hormone, and the performance improvements were "phenomenal".
The 38-year-old Dr Bonar's clients included a British boxing champion, a British Tour de France cyclist, and a martial arts competitor.
The Sunday Times' highly respected chief sportswriter David Walsh, who led the hunting of cycling cheat Lance Armstrong, followed up the story with a comment piece claiming that Premier League football had now joined a growing number of sports under suspicion of drug cheating.
Walsh wrote: "Maria Sharapova...her reputation and that of tennis are now on the line. And football: what about the Premier League? Up to now, we didn't know. That has changed. From the secretly taped conversations of Dr Mark Bonar it is clear the Premier League has not been immune from the scourge of doping.
"You don't have to believe every claim from Dr Bonar to know there is more than a little substance to his boasts of being a significant player in the performance enhancement game."