By Tom Degun at the Hilton Anatole in Dallas

LaShawn Merritt_15_MayMay 15 - Reigning Olympic 400 metres champion LaShawn Merritt admits that he has concerns about the prosthetic legs used by four-times Paralympic champion Oscar Pistorius – and has urged the International Association of Athletics Federations (IAAF) to keep a close eye on the situation to ensure the South African doesn't enjoy an unfair advantage over able-bodied athletes.

Pistorius (pictured below) , the 25-year-old double leg amputee from Johannesburg, is closing in on his goal of competing at both the Olympics and Paralympics at London 2012 thanks to his steadily improving times.

He became the first amputee athlete ever to battle for honours at the able-bodied World Athletics Championships at Daegu in 2011, reaching the 400m semi-finals and running as part of the South African 4x400m relay squad that secured silver.

But concerns have been raised about whether his 'blades' actually allow him to run faster than able-bodied athletes and fellow sprinter Merritt (pictured top, centre) believes the situation must be closely monitored.

"You know, he is getting better every year," the American told insideworldparasport here at the 2012 Team USA Media Summit.

"I haven't really been keeping up with it but I don't know how the judge made a ruling on it and what goes on with the prosthetic legs."

He added: "I'll tell you a story.

"I'm down at the IMG Academy [elite training] and a guy there told me that he has a friend who runs with two prosthetic legs.

"The guy ran 23 seconds over 200m.

"He got a couple of inches added to his legs, and in four months he ran 21 seconds.

"That is huge and I don't really know how to take that news.

"I just hope the federation [IAAF] keeps track of what is happening with him just so it is fair."

Oscar Pistorius_15_May
Merritt is no stranger to controversy: the 25-year-old from Virginia failed three drugs tests in 2009 when he tested positive for the banned steroid dehydroepiandrosterone.

The failed test was followed by the surprising confession from Merritt that he had consumed it via the use of a penis enlargement drug and he accepted a 21-month ban.

Merritt returned last year, winning silver in the 400m at the 2011 World Championships in Daegu behind Kirani James of Grenada; alongside the United States Olympic Committee (USOC) he helped overturn the International Olympic Committee's (IOC) Rule 45, or 'Osaka Rule', which banned any athlete serving a suspension of six months or more for doping violations from subsequent Olympic Games.

The move means that Merritt is eligible to defend his Olympic title at London 2012 – where he could face Pistorius.

It is unlikely, however, that Pistorius will run a fast enough time to realistically challenge Merritt in the Olympics, with the American a strong gold medal contender.

But Merritt is still concerned about the South African, who will do extremely well to even make the start line at the Olympics.

"You are talking about technology here," said Merritt.

"Technology gets better every day.

"I don't really think it about it a lot, I'm just focused on my own training, but anytime you talk about technology, you just don't know..."

To read our exclusive interview with Merritt on insidethegames, our sister website, click here.

Contact the writer of this story at [email protected]


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April 2012: Sir Philip Craven - Athletes must be given full credit in Paralympic sport, not their technology
September 2011: For the five per cent of critics, I have 95 per cent who support me, says Pistorius
September 2011: Angry Pistorius storms out of BBC interview
August 2011: Exclusive - Key scientist in Pistorius case insists he is running on level playing field
August 2011: Exclusive - Pistorius is getting "F1 advantage" and should not compete in Olympics, says South African sports scientist