In the final race of his illustrious career, Jamaican sprinter Usain Bolt fell down with a potential injury in the 4x100 relay final Saturday at the world championships. Running the anchor leg, Bolt pulled up favoring his left leg, limping and stumbling before tumbling to the track. After spending time lying down and being attended to by his relay teammates, Bolt got up and limped off the track. Host Great Britain finished first in 37.47 seconds, coming from behind to get past the United States (37.52), which finished second ahead of Japan (38.04). Jamaica was given a did not finish designation. Bolt's farewell track meet did not offer the ride off into the sunset that many expected. He finished third in last weekend's 100-meter dash final. The Associated Press contributed to this report.