Jamaica's Usain Bolt speaks to media after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt greets his supporters after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt speaks to media after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt greets his supporters after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt looks back after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt looks back after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt looks back after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt looks back after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt runs during the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

Jamaica's Usain Bolt looks back after he won the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

(From L-R) US athlete Justin Gatlin, Jamaica's Usain Bolt, and Britain James Dasaolu compete during the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

(From L-R) Jamaica's Nesta Carter, US athlete Justin Gatlin, Jamaica's Usain Bolt, Britain James Dasaolu, and Jamaica's Kemar Bailey-cole compete during the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

(From L-R) Jamaica's Nesta Carter, US athlete Justin Gatlin, Jamaica's Usain Bolt, Britain James Dasaolu, and Jamaica's Kemar Bailey-cole compete during the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

(From L-R) Jamaica's Nesta Carter, US athlete Justin Gatlin, Jamaica's Usain Bolt, Britain James Dasaolu, and Jamaica's Kemar Bailey-cole compete during the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)

(From L-R) US athlete Justin Gatlin, Jamaica's Usain Bolt, and Britain James Dasaolu compete during the men's 100m race at the Diamond League athletics meeting on September 6, 2013, in Brussels.(Xinhua/Gong Bing)