Farah stumbles his way into 5,000m final in double title defence
The consequences of that track fall in the 10,000m final on Saturday night are still there for Mo Farah.
"My shoulder. I feel it when I sleep at night. It hurts me, but I'll be alright," he said. But his powers of concentration were concerning him most as he progressed to the 5,000m final.
Farah stumbled again in his attempt to become the second man, after Finland's Lasse Viren, to retain the 10,000m and 5,000m titles, and he attributed that to focus. He regained his poise but American Hassan Mead, who clipped him as he fell, missed out on qualification.
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"I always seem to get tangled up somehow but I managed to stay on my feet. It's quite nerve-wracking getting back, you know? I'm just getting back into the zone again."
Farah just about retained his balance after his stumble to qualify safely in a heat won by Ethiopian Hagos Gebrhiwet, who is likely to be one of his chief rivals in the final.
Meanwhile, Caster Semenya qualified for the Olympic women's 800m semi-finals with supreme ease yesterday and was immediately plunged into a new gender controversy after a race rival questioned whether it was fair for her to compete.
Semenya will be favourite for Saturday's final but France's Justine Fedronic, who failed to advance from the heats, said her high testosterone levels meant it was not a fair fight.
"When you line up against someone like that, you know it's going to be a completely different ball game," Fedronic said.