World and Olympic sprint champion Usain Bolt has cancelled races in China and South Korea later this month and decided to bring his season to a close because of fatigue, the Jamaican wrote on his website on Friday.
The triple Olympic and world champion was scheduled to run 100 metres races in Shanghai on September 20 and Daegu on September 25 after participating at the world athletics final in Thessaloniki, Greece this weekend.
"I have been suffering from fatigue from as early as the Zurich meet and after careful discussions with my coach and management team, even with medical advice, we felt it necessary to close the season," read a statement on www.usainbolt.com.
"The season has been long and challenging. In addition, the risk of injury becomes greater and if I compete in the shape I am in, I may be at great risk," he added.
Bolt used a late surge to win the 100 metres at Zurich on August 28 and had been on the road since July 1.
The Shanghai Golden Grand Prix would have been his first race in China since his three gold medals and three world records at last year's Beijing Olympics.
"I know the Chinese fans will be disappointed, but I beg your understanding as I return home to rest and be prepared for next year's exploits. I thank all of you for your support and I look forward to coming to China next year," the 23-year-old said.
No mention was made of the Daegu race but the statement added that Bolt would be back in Jamaica on Monday "to participate in national activities and rest to prepare for next year's hectic schedule".
