Battye was a regular customer.

What followed, according to the judge presiding over the case, was "a hopelessly bungled attempt at an armed robbery" that was "violent and terrifying".

Twenty-six-year-old Battye pleaded guilty in the County Court in Bendigo on Monday to attempted armed robbery and recklessly causing injury in relation to the attack on November 2 last year.

The manager was working alone in the shop on Eaglehawk Road when Battye entered about 5.10pm with a metal bar concealed in his pants.

Battye took the bar out and approached the manager at the counter, demanding money.

The victim smiled because he thought it was a joke, but Battye hit the counter and tried to jump over it.

The victim pushed Battye back and ran to the gate of the counter to escape. Battye hit him on the left side of the head with the bar, causing him to temporarily lose sight in his eye.

CCTV footage played to the court showed a struggle ensued in which Battye grabbed the victim by the neck and pushed him against display shelves, while the victim tried to break free.

The victim lost balance and fell, before Battye got on top of him and punched him to the right eye.

Battye then ran out the door and the victim followed.

He went into a fish and chip shop, bleeding, and asked a woman to call triple-zero because he had been assaulted and robbed.

When police attended, the victim immediately identified Battye as his attacker.

In a victim impact statement read to the court by Crown prosecutor David Cordy, the post office manager said the incident left him afraid.

"I feel upset and vulnerable," he said.

He had always respected the post office customers, he said, and felt he was "stabbed in the back".

He said the crime affected his family life and the physical effects were ongoing, as he still suffered dizziness, vertigo and chest pain.

Battye was arrested later that month.

When interviewed, he admitted to the attempted armed robbery and causing injury.

He said he owed a $5000 drug debt and decided to steal the money to repay it.

He had consumed alcohol and methamphetamine in the hours beforehand, Battye told police, and decided to rob the post office after finding a metal pole while walking to his uncle's house.

He said the post office was the easiest place to target.

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Battye's defence counsel Eleanor Millar said her client had not set out to rob the post office that day.

Ms Millar told the court Battye's father died when he was four and he was orphaned at the age of 13, when his mother died.

From that time he stayed with family or in residential or foster care.

He struggled in school and was expelled at 13, after which time he had no further formal education until he undertook courses in prison.

The court heard Battye had a long history of substance abuse that began when he was a young adolescent and by the time of the offending he was using ice and alcohol, and cannabis daily.

Ms Millar said Battye had done courses in custody that included personal training and barista courses, and an alcohol and drugs course.

He was also employed in prison as a gardener.

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Ms Millar submitted Battye had already spent a significant period in custody - he had been on remand since his arrest - and a community corrections order would help him address his issues.

But Mr Cordy said the attack, while short-lived, was "nasty", and a sentence of time served with a corrections order would be "totally inadequate" given Battye's history.

Battye had committed earlier offences that included robbery and breached a community corrections order imposed last year.

Ms Millar said a psychological assessment confirmed a diagnosis of an intellectual disability, but Judge Michael Cahill said the psychologist offered "unprecise" opinions about the link between Battye's cognitive ability and his offending.

Judge Cahill said he accepted Battye was remorseful, and would take into account his difficult and disadvantaged background in his favour.

But he warned a sentence of time served and a community corrections was "out of the question".

He ordered a pre-sentence report be completed before sentencing Battye over the incident.

Battye will return to court in September.

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