Oscar Pistorius has dominated the headlines as he seeks to overturn his Olympic ban, but it is another South African Paralympian who has become the first amputee to qualify for an Olympic Games after Natalie Du Toit qualified for the 10-kilometres open water event.

Du Toit, 24, who lost her left leg in a motor-scooter accident in 2001, has already competed in the pool at the 2002 Commonwealth Games, but she surprised the field at the Open Water World Championships in Seville on Saturday by finishing fourth in a field of 50, in the toughest endurance event in swimming, which makes its debut at the Beijing Olympics. Du Toit finished in 2hr 2min 7.8sec, just 5.1seconds behind Larisa Ilchenko, of Russia, the winner.

Unlike Pistorius, Du Toit uses no prosthetics, which are banned in Paralympic swimming. More than an ounce of her extra determination has come from being so overshadowed in her homeland by Pistorius, but she is set to become a star in Beijing, competing in the Olympic Games and, two weeks later, in the Paralympics. She can next be seen at the Paralympic World Cup in Manchester, which begins on Wednesday and will be shown on BBC television.

But her case, like that of Pistorius, still raises questions for a Paralympic movement trying to define itself. Does it become a feeder event for the Olympics? Will its more telegenic events be absorbed into the Olympics?

As Pistorius awaits the results of his appeal at the Court of Arbitration for Sport, in Lausanne, Switzerland, last week, Britain's greatest Paralympian said that he should not be allowed to compete. “He's been able to highlight what the Paralympics is, I just don't think it is about whether he has an advantage or disadvantage, he's just too different.” Tanni Grey-Thompson said. “I'd like Oscar to be a Paralympian and not an Olympian. I can see why he wants to go to the Olympics, for the competition, fame and the money, but I'd like to see him get that at the Paralympics and I think London [2012 Paralympics] will be able to deliver that. The London Paralympics is going to be a mainstream event.”

Grey-Thompson, who competed in five Paralympics, winning a British record of 11 gold medals, has never felt comfortable with the way her event, wheelchair racing, was shoehorned into the Olympics. It was a demonstration event in Atlanta, Sydney and Athens, but medals were not awarded.

Phil Craven, president of the International Paralympic Committee, supports the desire of Paralympians to compete at the Olympics. “There are two things here,” he said. “Oscar is a great athlete. As a great athlete, he wishes to stretch himself to the limit. He's in a class of his own in the Paralympics. I don't think that will be the case for ever, but it is understandable that he wishes to run against the fastest in the world. Those fastest athletes, at the moment, will be competing in the Olympic Games.

“On the other hand, we fully respect the governance and authority of the IAAF [International Association of Athletics Federations, which banned Pistorius in January] to set the rules and Oscar has to comply by those.”

Craven's use of “at the moment” is interesting. For an amputee to be banned because he has an advantage was science fiction before Pistorius and Du Toit. But, because of technology, Pistorius's case raises the possibility of sprinters winning the Paralympics in faster times than in the Olympics. If someone breaks 9.5 seconds for the 100 metres at the Paralympics in, say, Bombay 2032, the event starts to look less a silent partner.

Wheelchair racing has already outstripped the speeds of running for every event beyond 400 metres. As Grey-Thompson would argue, the Paralympics is not lesser or greater than the Olympics, it is just different, but more Paralympians will surely be inspired to follow by the rise of Pistorius and Du Toit.

All you need to know

The Paralympic World Cup will include athletics, swimming, track cycling and wheelchair basketball.

The competition was created to provide an annual world-class multisport event at which elite athletes could compete in between the four-yearly Paralympic Games.

340 of the world's best Paralympic athletes, from 47 countries, competed for 143 medals in four sports at last year's Paralympic World Cup.

The BBC will again cover the event as it continues to showcase elite disability sport before this summer's Paralympics.

Tickets are available on paralympicworldcup.com or by phone on 0871 2305595 or text WORLDCUP3 to 84880 for more information.