The Court of Arbitration for Sport yesterday ruled that the man nicknamd 'Blade runner' is eligible to race against able-bodied athletes - overturning a ban by the International Association of Athletics Federations.

The 400-metre Paralympic world record holder of 46.56 seconds must now reach the Olympic qualifying standard of of 45.55, although he can be picked for the South African relay squad immediately.

'I am ecstatic,' said the 21-year-old. 'When I found out, I cried.

'It is a battle that has been going on for far too long. It's a great day for sport. I think this day is going to go down in history for the equality of disabled people.'

He runs on carbon-fibre blades, after having his legs amputated below the knee when he was 11 months old because he was born without fibula bones in his legs.

The IAAF had banned the 400m runner from all competitions involving able-bodied athletes, because of claims that the artificial legs he uses give him an unfair advantage.

It was not until March last year that the world body voted in an amendment to IAAF rule 144.2 (e) - for the purpose of regulating technical devices 'that incorporate springs, wheels or any other element that provides the user with an advantage over another athlete not using such a device'.

But the CAS' panel of three arbitrators was unanimously 'not persuaded that there was sufficient evidence of any metabolic advantage in favour of a double amputee using the Cheetah Flex-Foot'.

Pistorius said he will be running in both able-bodied and Paralympic events before Beijing.

'A lot of the time this year, we've devoted to the court case,' he said. 'Now, when I get home, my time can be dedicated to training.

'I am going to have to start thinking about getting my body in shape to run those qualifying times. I am hopeful there will be enough time, but it is going to be very difficult.'

The verdict also clears Pistorius to dedicate himself to competing at the 2012 London Olympics.

The IAAF accepted the binding decision. Said its president Lamine Diack: 'Oscar will be welcomed wherever he competes this summer.

'He is an inspirational man, and we look forward to admiring his achievements in the future.'

The IAAF based its January decision on studies by German professor Gert-Peter Brueggemann, who said the blades were energy-efficient.

The athlete's lawyers countered with tests - conducted by a team led by Massachusetts Institute of Technology professor Hugh M.Herr - which showed he does not gain any advantage over able-bodied runners.

The CAS stated that its decision would not open the floodgates, emphasising that the decision is 'limited' to the Pistorius case. It said: 'It follows that this decision has no application to the eligibility of any other athletes or any other model of prosthetic limb.'

Despite his disability, Pistorius went through school as a keen athlete - taking part in rugby, water polo, tennis and wrestling.

He took up running competitively only in January 2004, after he suffered a knee injury while playing rugby.

Only a few months later, aided by his prosthetic limbs, he went on to win Paralympic gold in the 200m at the Athens Games, where he also won bronze in the 100m.

AGENCE FRANCE-PRESSE, ASSOCIATED PRESS