MOSCOW Allyson Felix flew out of the blocks, same as usual. She tried to settle into her rhythm around the turn, as she always has.
Then everything went horribly wrong for the American sprinter. She suddenly screamed and began hopping before falling to the track with a torn hamstring.
There went her world championships. There possibly went her season, too.
As Jamaica's Shelly-Ann Fraser-Pryce won the 200-meter race Friday night, Felix, the Olympic champion in the event, was at the far end of the stadium being tended to by medical personnel.
And as Fraser-Pryce dropped to the track in celebration, Felix was being carried off by her brother, Wes. Felix had big plans, too, possibly winning three medals one in her signature event, the 200, along with maybe two more in the 4x100 and 4x400 relays.
"I'm extremely devastated," Felix said in a statement. "I was really hoping to go out there and put together a great race."
It was setting up to be an epic showdown.
Fraser-Pryce got off to a fast start, but Felix is known for her finishes.
She never got a chance to kick it into gear.
Suddenly, she was out of the race. From there, it was all Fraser-Pryce, as she won in 22.17 seconds. Murielle Ahoure of Ivory Coast was second, a fraction of a second ahead of Nigeria's Blessing Okagbare, a silver medalist in the long jump.
"I heard when she screamed out, but I was really focused on what I wanted," Fraser-Pryce said. "I decided I was running that corner and I didn't care who you were, if you were Usain Bolt behind me, I couldn't care less, I was running like my life depended on it."
The long-term status of Felix remains murky.
"It is a serious injury, but I don't know exactly to what extent," she said.
Everything went right for the U.S. men's 4x400 relay team as the Americans won their fifth straight world title in convincing fashion with LaShawn Merritt strolling across the finish line.
"We went out and got the job done," said Merritt, who also won the 400 on Tuesday. "We train to win."
Everyone else trains to win, too, but rarely are they hurt by their equipment, like Bolt was in a practice session.
The world's fastest man had a clumsy moment in Moscow, dropping the blocks on his foot as he carried them.
No big deal, the Jamaican simply taped his tender right foot and dominated yet again, winning his semifinal heat in the 200.
Even with a bum wheel, he's still nearly impossible to catch. And now he's promising full-out effort for the final today, no letting off the accelerator.
"I'm not going to hold anything back. I'm going to go out there and push myself, see how fast I can run," Bolt said.
These days, England's Mo Farah is just as dominant in the distance events as Bolt is in the sprints. Farah added a 5,000 title to his 10,000, giving him another double just like at the London Olympics.
In other finals, Aleksandr Menkov of Russia won the men's long jump title, with four-time champion Dwight Phillips 11th. Olympic champion Tatyana Lysenko of Russia captured the hammer throw.