Victory for the 25-year-old South African never looked in any doubt from the gun, as he struck out on his own to lead coming into the last half-lap and was roared across the line by the packed 80,000-capacity Olympic Stadium in 46.68sec.
US athletes Blake Leeper took silver in 50.14sec with David Prince in bronze on 50.61.
Pistorius -- the only man in the field to run under 50sec for the one-lap sprint and the first double-amputee to compete at the Olympics last month -- won the 100m, 200m and 400m treble in Beijing four years ago.
But he lost both of the shorter sprint titles to Britain's Jonnie Peacock and Alan Oliveira of Brazil.
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Definitely, they worked equally hard to achieve their success
No way! Far fewer opponents and far more events at the Paralympics to warrant equal payouts
Touchy subject, not getting involved...
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72% Definitely, they worked equally hard to achieve their success
20% No way! Far fewer opponents and far more events at the Paralympics to warrant equal payouts
8% Touchy subject, not getting involved...
Vote Archive
ProvinceFan gives his opinion on the Heyneke Meyer's most recent Springbok squad announced by SA Rugby.
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