South Africa's Oscar Pistorius has made history at the Olympic Stadium in London by becoming the first athlete with prosthetic legs to compete at an Olympic Games. The four-time Paralympic champion, known as the blade runner, finished second in heat one of the 400m behind the Dominican Republic's Luguelin Santos, in a time of 45.44 seconds. The result was enough for him to qualify for the semi-finals of the one-lap event.Australia's Steven Solomon won heat six with a personal best of 45.18, edging Lalonde Gordon of Trinidad and Tobago.Defending champion and gold-medal favourite LaShawn Merritt's challenge ended when he pulled up on the backstretch of the same heat clutching his left hamstring.Pistorius, 25, races with carbon fibre prosthetic blades after being born without a fibula in both legs.