Rudisha back on top of the world, Dibaba dominant

David Lekuta Rudisha of Kenya reacts after winning the men's 800m event during the 15th IAAF World Championships at the National Stadium in Beijing, China August 25, 2015. REUTERS/Lucy Nicholson

BEIJING (Reuters) - David Rudisha strained every sinew to win gold, Genzebe Dibaba dominated in the way the Kenyan once did and Usain Bolt's second sprint showdown with Justin Gatlin moved a step closer at the world athletics championships on Tuesday.

While Rudisha's 800 metres victory was not a patch on the brilliant run that won him gold in a world record time at the London Olympics, there was a reminder of one of the great nights of that Games when Britain's Greg Rutherford won long jump gold.