Ethiopia's Etenesh Diro got tangled up with two other runners in Saturday's 3,000m women's Olympic steeplechase and stopped to tear off her damaged right shoe and sock, but she kept on running to finish seventh.
Diro, a 25-year-old who placed fifth in the event at the 2012 London Games, had been seen as a leading medal contender before her mishap.
She broke down in tears, leaving without speaking to reporters after failing to advance to the next round. Her time of 9 minutes 34.7 seconds was more than 20 seconds off her personal best.
Australia's Genevieve Lacaze, who finished second with a time of 9:26.5 to qualify for the next round, complained that the mishap had obstructed the track.
"She was like a road block," the 27-year-old said.
"Someone ripped out her heel and, instead of getting out of the way - I guess you don't think about others too much when you're in the Olympics - she just stopped and was a roadblock for about four girls."
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