The boy, 14, had admitted causing grievous bodily harm with intent, attempted robbery, and possessing a knife.
The incident, on Tuesday June 8 around 7.15pm, happened on Dugald Drummond Street, near to Greetham Street, during which a man in his 20s was left with knife injuries to his legs.
Police said at the time of the offence the victim avoided suffering life-threatening injuries.
The defendant was accused of attempting to rob an unknown value of drugs from him.
The boy was subsequently charged with the offences before pleading guilty at Portsmouth Youth Court on June 11.
He was then remanded to secure accommodation for sentencing on Friday.
However, during the hearing, it was confirmed by the boy’s solicitor that an application to withdraw those pleas would be put forward in writing within the next two weeks after a further review of the evidence.
The chair of the bench agreed to allow the application but said it was no indication it would be granted.
‘The defence are entitled to make the application,’ he said.
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It means the teenager, who admitted a new charge of robbing a £300 e-scooter on June 3 in Portsmouth, will now appear at court on July 15.
A message from the Editor, Mark Waldron
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