Only one person has been able to stop Usain Bolt at the world championships this week.
The Jamaican sprinter won the 200 meters on Thursday, finishing comfortably ahead of rival Justin Gatlin, to bookend his earlier victory in the 100.
It was only afterward, as he took a victory lap around Bird's Nest Stadium, that Bolt was hit from behind by a photographer on a Segway and sent tumbling to the track.
He bounced up unhurt, smiling. Winning has a way of smoothing over the small bumps.
"There was no doubt," Bolt said of his 200 victory. "I told you guys that I would do it."
This had been a difficult stretch for the greatest sprinter in history. Injuries had kept him off the track at various times over the past two years, and he had looked rusty heading into the championships.
On Thursday, he opened a wide enough lead coming around the turn to ease up at the end. Gatlin took the silver, and Anaso Jobodwana of South Africa was third.
Bolt has now doubled at multiple Olympics and world championships. He has a shot at another gold in the 400-meter relay later this week.
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