Against one of the greatest fields ever assembled, Usain Bolt won the 100m final with relative ease, retaining his gold medal from Beijing. Here's the video.
Bolt's 9.63 was a new Olympic record and a .06-second improvement on his gold-medal time from Beijing. He becomes the first man since Carl Lewis in 1984 and '88 to repeat as Olympic champion. Blake was second, with a 9.75; Gatlin took bronze with a 9.79.
