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. Felix had big plans, possibly winning three medals — one in her signature event, the 200, along with maybe two more in the 4 x 100 and 4 x 400 relays. Full story for BostonGlobe.com subscribers.