Usain Bolt (2nd R) of Jamaica competes during the men's 100m at the IAAF Diamond League in Zurich, Switzerland, on August 29, 2013. Usain Bolt claimed the champion with 9.90 seconds. (Xinhua/Wang Siwei)

Usain Bolt of Jamaica competes during the men's 100m at the IAAF Diamond League in Zurich, Switzerland, on August 29, 2013. Usain Bolt claimed the champion with 9.90 seconds. (Xinhua/Wang Siwei)

Usain Bolt (R) of Jamaica looks on during the men's 100m at the IAAF Diamond League in Zurich, Switzerland, on August 29, 2013. Usain Bolt claimed the champion with 9.90 seconds. (Xinhua/Wang Siwei)

Usain Bolt (below R) of Jamaica reacts after the men's 100m at the IAAF Diamond League in Zurich, Switzerland, on August 29, 2013. Usain Bolt claimed the champion with 9.90 seconds. (Xinhua/Wang Siwei)

Usain Bolt of Jamaica reacts during the men's 100m at the IAAF Diamond League in Zurich, Switzerland, on August 29, 2013. Usain Bolt claimed the champion with 9.90 seconds. (Xinhua/Wang Siwei)