2012 — Usain Bolt is a perfect 3 for 3 at the London Olympics — three events, three victories — just like Beijing four years ago. Almost even with the last U.S. runner when he got the baton for the anchor leg of the 4x100 meters, Bolt steadily pulls away down the stretch, gritting his teeth and leaning at the line to cap his perfect Summer Games by leading Jamaica to victory in a world-record 36.84 seconds. Allyson Felix wins her third gold medal, giving the United States a 20-meter lead after the second leg of the 4x400-meter relay. DeeDee Trotter, Felix, Francena McCorory and Sanya Richards-Ross bring home the victory for the Americans’ fifth straight Olympic title in the event.
Jamaica's Usain Bolt celebrates as he finishes ahead of United States' Ryan Bailey in the men's 4 x 100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds.(AP Photo/Martin Meissner)