Double Olympic 10,000m champion Mo Farah will not be at this summer's Games in Tokyo, having missed out on a last-ditch qualification.
The gold medallist at the London and Rio Olympics was running in a special trial race at British Athletics Championships in Manchester, with the target of 27 minutes and 28 seconds.
But the 38-year-old has been struggling with an ankle injury, and finished just over 19 seconds slower than the requirement.
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"I've been lucky enough to have had the long career I've had," he said after the race. "I'm very grateful but that's all I had today."
When asked if that could be his final race, he replied: "If I can't compete with the best I'm not just going there to finish in a final. Tonight shows it's not good enough."
He was running alongside training partner Bashir Abdi and pacemaker David McNeil within a field of 11 on the start line.
In his previous attempt, at the European 10,000m Cup in Birmingham, he was 22 seconds away from the target time.
He had stepped away from track running over the past few years, switching his attentions to the marathon, but returned to the 10,000m with a view to retiring after Tokyo.
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