But South Africa’s Oscar Pistorius made history when he became the first double amputee to compete in an athletics event, qualifying for the semi-finals with a season’s best of 45.44sec.

Merritt stopped running after 250 metres of his heat and crossed the line at walking pace. “This was my life’s race,” the 26-year-old said. “I have been around a long time, but I am still young.”