David Rudisha of Kenya smashes the world record and takes gold in the mens 800m final held at the Olympic Stadium in London, England on the 9th August 2012 ©Barry Aldworth/BackpagePix

Warren Weir (Bronze left) Usain Bolt (Gold centre) and Yohan Blake (silver right) celebrate after their clean sweep of the medals in the Mens 200m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

David Rudisha of Kenya breaks the world record in winning the mens 800m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Pamela Jelimo of Kenya competes in the womens 800m semifinal during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

David Rudisha of Kenya smashes the world record and takes gold in the mens 800m final held at the Olympic Stadium in London, England on the 9th August 2012 ©Barry Aldworth/BackpagePix

Caster Semenya wins her womens 800m semifinal heat, to advance to the final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Nijel Amos of Botswana wins silver in the mens 800m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Pamela Jelimo of Kenya competes in the womens 800m semifinal during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Oscar Pistorious of South Africa waits for his team mate after his team mate fell out of the 4 x 400 m relay held at the Olympic Stadium in London, England on the 8th August 2012 ©Barry Aldworth/BackpagePix

Sunette Viljoen of South Africa in the women's javelin final held at the Olympic Stadium in London, England on the 9th August 2012 ©Barry Aldworth/BackpagePix

David Rudisha of Kenya breaks the world record in winning the mens 800m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Cherono Koech of Kenya competes in the womens 800m semifinal during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

David Rudisha breaks the world record in winning the mens 800m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Usain Bolt wins gold in the Mens 200m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Sunette Viljoen competes in the womens javelin final, finishes fourth during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix

Warren Weir (Bronze left) and Usain Bolt (Gold centre) celebrate after their clean sweep of the medals in the Mens 200m final during the Olympic Games Athletics at the Olympic Park, London on 09 August 2012 ©Gavin Barker/BackpagePix