Bolt tweeted Friday night that he has a Grade-1 tear in his left hamstring.
He said he first felt discomfort in his leg after he ran in the first round of qualifying for the 100 meters Thursday. After he won his semifinal heat Friday evening he felt pain again and saw a doctor, who diagnosed the tear.
"I will seek treatment immediately and hope to show fitness at the London Anniversary Games on July 22 to earn selection for the Olympic Games in Rio," Bolt, the world record holder at 100 and 200 meters, said.
Bolt said he submitted a medical exemption ahead of Friday night's 100 meter final, asking to miss the final and the rest of the events at Jamaica's Olympic trials.
Yohan Blake, the silver medalist at the London Olympics in 2012, won the 100 meters on Friday, running an impressive 9.95.
Three weeks ago, Bolt, 29, ran the second-fastest time in the world this year, clocking 9.88 in the 100 meters at a meet in Jamaica. France's Jimmy Vicaut tops the 2016 list of best times in the event, running a European record 9.86 on June 7 in his home country.
The Jamaican athletics federation's regulations provide a way Bolt could run the 100 meters in Rio.
"Athletes who are ranked/listed in the top three in the world for their event who are ill or injured at the time of the national championships and are granted an exemption from competing at the championships may still be considered for selection provided that they are able to prove their world ranking form prior to the final submission of the entries for the competition."
Bolt has not run the 200 meters this year, so it remains unclear if he will be able to run that event at the Olympics if healthy.
The athletics schedule at the Olympics begins August 12.

Source: http://lifedrama.com.ng/usain-bolt-withdraws-from-jamaican-championships/