Pistorius (25) is favourite to retain his T44 400m title for single and double below-the-knee amputee sprinters, being the only man to run under 50sec in the final, which ends the athletics action at the Olympic Stadium.
Simmonds, who shot to fame as a 13-year-old in Beijing when she won the S6 100m and 400m double, is looking to repeat the feat — and cement Britain’s second spot in the medals — after retaining her title in the longer distance.
Sunday sees the quadrennial festival of disabled sport spill out onto the streets of the British capital, with four marathon races starting and finishing on the Mall outside Queen Elizabeth II’s London residence, Buckingham Palace.
Large crowds are expected as the best wheelchair, amputee, blind and visually-impaired 26.2-mile (42-kilometre) racers go past key landmarks in the city, including the Tower of London and the British parliament.
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