Callan Lakeman, 19, of Park St, Port Macquarie, was convicted on Monday of behaving in an offensive manner in a public place.

Port Macquarie Local Court magistrate Wayne Evans said Lakeman and others needed to be deterred from such behaviour.

"In this day and age, the shock value is diminished by the fact of what we see in the press and in the movies," he said. "Hopefully it's a wake-up call ... because really, the community doesn't find anything amusing in this."

According to police facts tendered in court, Lakeman jumped the fence at the Port Macquarie Regional Stadium just before 9pm on February 15 and ran nude across the field.

The Sydney Roosters-Port Macquarie Sharks match had concluded when Lakeman and another man ran from north to south on the field and in front of the grandstand to yelling and cheering from the substantial crowd.

Lakeman then left the ground and police found him standing near a toilet block with his hands covering his genitals.

When he saw the police, Lakeman ran in the opposite direction and hid in the female toilets.

He was found sitting on a toilet, naked from the waist down.

A friend had given him a shirt before he entered the toilet block.

Solicitor Matthew Lindeman said Lakeman was "usually quite shy" and the behaviour was out of character.

He said Lakeman went to the football with a large group of friends to celebrate his birthday and consumed a large quantity of alcohol.

"By his own admissions he's no male model," Mr Lindeman said.

"He instructs me that when he saw himself on television the next day he was very, very embarrassed about it."

Mr Lindeman said the incident was inappropriate at a family event.

"He's certainly embarrassed himself and his family on a very large stage," he said.

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