Glenn Archer is revered as one of the toughest players to have donned an AFL jumper but his assault on a runner at his son’s footy match has been slammed by a magistrate as “abhorrent” and a bad example for kids.

The former North Melbourne star and club board member was on Friday fined $2000 for punching the volunteer official and ordered to replace his broken glasses.

Although he pleaded guilty, Archer claims he was not judged on the full story and will appeal the penalty.

The 44-year-old admitted in Heidelberg Magistrates’ Court to assaulting Jamie Chilcot at the suburb’s football ground on June 25.

“It is an abhorrent thing to do,” Magistrate Cathy Lamble said as she convicted Archer.

“It sets such a bad example for children playing sport and a bad example to other parents.

“They should leave it to the umpires and other officials on the ground.”

Archer was watching his son Jackson play in the under-15s for Park Orchards when a scuffle broke out between two players.

The ex-Kangaroo ran onto the ground in a bid to break up the fight before engaging in a heated exchange with two umpires.

As players left the ground at half time, Archer clashed with Mr Chilcot, who was volunteering as a runner to deliver coaching instructions to players.

“The accused punched Chilcot, striking the right side of his face,” prosecutor Matt Toohey told court in an agreed set of facts.

“The force of the blow caused the arm of the glasses he was wearing to break off.”

In addition to the fine Archer was ordered to pay $955 to replace the specs.

“Don’t I get to defend myself? You haven’t got the full story,” Archer said as the matter drew to a close.

“The decision’s been made, Mr Archer,” Ms Lamble replied.

Outside court Archer said he would appeal the penalty.

“I actually find it crazy that someone can read out three per cent of a story and then you’re judged on that,” he told reporters.

North Melbourne acknowledged in a statement that Archer was apologetic and said they would take no action.

“Glenn is able to continue in his role as a director,” it said.

Archer played 311 games for the Kangaroos and was named in the club’s Team of the Century.

The famously fearless defender won the Robert Rose Award for the AFL’s most courageous player a record six times and was awarded the 1996 Norm Smith Medal.

The court heard this was the third time Archer had been accused of assault, after being charged in 1994 and convicted in 1999.