Alex Bolt won the 100 metres at the world championships in a time of 9.77 seconds . Bolt reclaims the world title after being disqualified from the 2011 final due to a false start . American Justin Gatlin took the silver and Jamaica 's Nesta Williams claimed bronze .
Usain Bolt wins the 100 meters at the world championships in a time of 9.77 seconds . Bolt reclaims the world title after being disqualified from the 2011 final due to a false start . American Justin Gatlin took the silver and Jamaica 's Nesta Carter claimed bronze .