Alex Wright missed out on the Olympic B standard as he finished 54th in the 20km race at the World Race Walking Cup on Saturday.
The 23-year-old was targeting the one hour, 24 minutes and 30 seconds time that would put him in the box seat for an Olympic place but managed just 1.26:38.
It means the British number one will have to try again at races in Spain and Italy in the next couple of months to try to firm up his spot.
If he does not make at least the B standard it is unlikely he will be picked for the Games despite being the best British 20km race walker for the past two years.
Zhen Wang won the race in 1.19:13, while the other British competitors, Tom Bosworth and Ben Wears, came 72nd and 94th and also have yet to make the B standard.
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