LONDON -- Usain Bolt put an exclamation point on a legendary encore Olympic performance, anchoring the Jamaican 4x100-meter relay to another record-setting, gold medal in the final track event of the Games on Saturday night.
Four years after setting three world records and winning three gold medals in Beijing, Bolt won both the 100 and 200 meters again, then sprinted the final straightaway as Jamaica became the first foursome in history to eclipse 37 seconds.
Nesta Carter, Michael Frater, Yohan Blake and Bolt crossed the finish line in 36.84 seconds, breaking its own world record of 37.04 from 2011 and its Olympic mark of 37.10, and finishing well ahead of silver medalist United States.
Bolt will go home with three more gold medals, giving him six in two Olympics and cementing his status as history's greatest sprinter.
The American quartet of Trell Kimmons, Justin Gatlin, Tyson Gay and Ryan Bailey ran a U.S.-record time of 37.04.
The U.S. strategy clearly was to try generating enough of a lead through the first three legs -- with 100-meter finalists Gatlin and Gay running second and third -- that Bailey would have a cushion against Bolt.
Blake trailed when he got the baton, but overtook Gay on the turn and gave Bolt slight lead entering the stretch.
Trinidad and Tobago won the bronze medal after Canada was disqualified.