Beijing: Usain Bolt capped a memorable world championships by winning a third gold medal on Saturday as anchor of the Jamaican 4x100m relay team, while fierce rivals the United States were disqualified.
Bolt ran the final leg of the relay at a packed Bird`s Nest stadium, hurtling through the line in 37.36 seconds after teammates Nesta Carter, Asafa Powell and Nickel Ashmeade had successfully got the baton around.
The victory gave Bolt his 11th world gold medal -- the only one missing from his collection being the 100m in the 2011 Daegu worlds when he was disqualified after a false start.
The US quartet of 100m bronze and silver medallists Trayvon Bromell and Justin Gatlin, and fellow finalists Tyson Gay and Mike Rodgers were initially awarded silver but later disqualified.
China, headed by individual 100m finalist Bingtian Su, delighted the home crowd when they were upgraded to a shock silver in 38.01sec while Canada were awarded bronze (38.13).
Double Olympic champion Shelly-Ann Fraser-Pryce anchored Jamaica to their second successive world title in the women`s 4x100 metres on Saturday.
Fraser-Pryce, who won the 100 metres individual title in Beijing, left Jasmine Todd in her wake as the Jamaican quartet overpowered Olympic champions the United States to clock a championship best 41.07 seconds. The Americans took silver in 41.68.
The Jamaicans led from the gun, Veronica Campbell-Brown producing a blistering start, which Natasha Morrison built on in the second leg and Fraser-Pryce added the final flourish to bring the baton home in style.