A man who punched a female police officer in the face after drinking too many beers in a private function room at an AFL match has been sentenced to six months' jail under mandatory sentencing laws designed to protect emergency service workers.

Key points: Macintire was refused re-entry to Geelong's Kardinia Park after a security guard noticed he was drunk, swaying and unsteady on his feet

Macintire was refused re-entry to Geelong's Kardinia Park after a security guard noticed he was drunk, swaying and unsteady on his feet He punched the security guard in the face, was capsicum-sprayed by police and then punched a female police officer in the head

He punched the security guard in the face, was capsicum-sprayed by police and then punched a female police officer in the head Magistrate Ann McGarvie said his mandatory six-month jail term, despite never having been in trouble with the law before, should serve as a warning to others not to assault emergency workers.

Darron Macintire, 46, had never been in trouble with the law before he assaulted the senior constable and a security guard at the Geelong home game against North Melbourne in August last year.

Macintire's defence lawyer conceded there was nothing he could do to spare his client from jail, and his early guilty plea, long-term employment history with a trucking company, good references and otherwise "blameless existence", were not enough to shield him from the mandatory sentencing laws.

"We don't have special reasons. The legislation is quite limited in what constitutes special reasons," he said.

"The message is clear that emergency workers cannot and should not be treated as punching bags."

The court heard Macintire had been in the Pivot Room at Kardinia Park when he went outside for a cigarette with colleagues at three-quarter time.

When a security guard noticed Macintire was swaying and unstable on his feet he refused him re-entry to the stadium.

Police prosecutor Alana Groves said Macintire punched the male security guard on the chin.

Two female officers then attempted to handcuff Macintire, but he resisted and one deployed OC spray.

Macintire then turned and hit the senior constable with full force using a clenched fist, striking her on the temple and cheekbone, the court heard.

A member of the public put Macintire in a headlock and restrained him on the ground.

The prosecutor said another member of the public, who had seen Macintire refused entry, filmed the incident on their mobile phone because "he felt like something was going to happen".

The footage was released by the court on Wednesday.

Police officer rethinking her career

The court heard the senior constable was taken to hospital where she was given pain relief and ice packs for bruising.

Nine days later, she still had persistent headaches and concussion symptoms including decreased concentration and fatigue.

Magistrate Ann McGarvie said the victim had lost trust in the public and may not be able to continue working as a police officer.

"She's rethinking her career that she loves and that is such a shame," Ms McGarvie said.

"The community wants to encourage the police force to be as varied, in the sense of there being more women … so that it is representative of our general community."

Ms McGarvie said it was critical for public safety that police officers were able to do their job without fear of assault.

"She [the victim] has to deal with members of the public and has to maintain order when members of the public are out of order," she said.

"It's her job to try and prevent anyone else being hurt … to ensure order is maintained when people, particularly at the football, have had too much to drink."

Darron Macintire pleaded guilty to four charges in December. ( ABC News )

Ms McGarvie said she hoped the case would be a lesson to the wider community.

"It is a serious offence. I have no other option than to sentence you to a term of imprisonment," she told Macintire.

"No one is saying you are a bad person because clearly in your past you were of good character.

"The [mandatory sentencing law] is not only for people who are of bad character or are very violent. It applies to all of us."

Macintire was sentenced to six months' jail and showed no emotion as he was taken into custody.