Boxing: Do rope-a-dopes rule ring?

Sweet science fights rumours of illegal drugs used to rise up weight divisions

Manny Pacquiao, acknowledged as the world's best fighter, was defending more than his title against Ghana's Joshua Clottey in Dallas late last night. Also at stake was his integrity after allegations that his phenomenal rise from flyweight to welterweight has been fuelled by drugs. Pacquiao's emphatic denial – "I don't even know what a steroid is" – is in the wake of rumours spreading that boxing now has a major doping problem.

It used to be that boxing's only concern over drug abuse was the use of diuretics by fighters trying to make the weight. Now the finger of suspicion has pointed in the direction of those such as Pacquiao, Evander Holyfield, Shane Mosley, Oscar De La Hoya and Roy Jones (who all deny taking steroids), who piled on the pounds to move into higher weight divisions.

The speculation has even embraced Amir Khan. As Floyd Mayweather did with Pacquiao, Paulie Malignaggi has accused Khan of using steroids, "because he trains with the Pac Man". No doubt this is designed to generate interest in their forthcoming fight but the groundless insinuation angered Khan, whose trainer Freddie Roach dismisses Malignaggi as "an ass".

So is boxing drugs-infested? Enter the ring Victor Conte of Balco infamy, the man who provided Dwain Chambers and five-times Olympic gold medal sprinter Marion Jones, among others, with performance-enhancing drugs. He claims drug use is rife due to lax regulation, notably in the US. The problem is that professional boxing is one of the few sports not regulated by a single governing body. The US has numerous commissions with different rules. "I don't believe pro boxing wants to know how rampant the use of drugs is," says Conte. "Testing in boxing is completely and totally inept." It was Conte who first accused Mosley of taking performance-enhancing drugs when he utilised Balco's services. Mosley says he believed the products he was using were legal vitamins, though in May 2008 Mosley's former trainer told a grand jury that in 2003 the boxer injected himself with doping agent EPO as he prepared for a fight against De La Hoya – whose own preparations have now been called into question in a new book by Thomas Hauser.

Mosley never tested positive and was not sanctioned. But even when the world light-heavyweight champion Jones did test positive for androstenedione in 2000 he was allowed to keep his titles and wasn't fined or suspended. Five years later, James Toney beat John Ruiz to win the WBA heavyweight title but tested positive for the steroid stanozolol. He received only a 90-day ban.

The promoter Frank Warren, commenting on how the Mayweather-Pacquiao megabucks fight fell apart because of Mayweather's insistence on blood testing for the Filipino, says there could be an increasing problem. There are whispers that a British fighter and his trainer have taken human growth hormone. "HGH adds bulk and, if taken in excessive amount, is seen by some idiots as the perfect pill for fighters who want to move quickly into higher weight divisions," Warren says. "I would like to see British boxers randomly tested for HGH."

The highest-profile boxer who failed a drugs test in this country is a woman, Liverpool's Jade Mellor, the ABA featherweight champion. Last July she tested positive for a diuretic but claimed she took it to help make weight because of the onset of her period on the morning of her ABA final. A masking agent was also present. Her appeal failed and she has been suspended for two years.

One certainty is that Britain's past and present Olympic squads are all clean. "As a top amateur you were tested regularly," says the Olympic gold medallist James DeGale. "When I won the Olympic gold I had both a blood and urine test. It's pretty strict. But so far I haven't been tested as a pro."