Jamaican Usain Bolt retained his Olympic 100m crown in spectacular style on Sunday, scorching to the second-fastest time ever run at 9.63 seconds and becoming the first man to win back-to-back titles on the track.
Bolt's 9.58-second run to win the 2009 world title is the quicker run and Sunday's brilliant display proved he had completely recovered from the hamstring problems that had given a sliver of hope to his rivals in the build-up to one of the most eagerly-anticipated races in history.