MELBOURNE forward Jeff Garlett has escaped conviction over a "pretty horrific" brawl during which he was knocked unconscious on his 25th birthday.

Garlett pleaded guilty in the Melbourne Magistrate's Court on Monday to one charge of behaving in a riotous manner over the August 3 brawl in Melbourne’s CBD last year involving dozens of men.

He was placed on a diversion program until mid-November and must continue volunteer work mentoring children.

Garlett was fined $5000 by his then club Carlton and missed games in the lead-up to the 2014 finals.

Prosecutor Geoff Adams described the incident as "pretty horrific".

Garlett's lawyer Bernie Balmer said Garlett, who wouldn't comment, was now a different person, and was keen to be a role model to indigenous youth.

"It's all behind him," Balmer told reporters.

"Keep in mind, Jeff was absolutely knocked out on this night so that's a penalty in itself."

Mr Garlett's cousin Gerald Garlett pleaded guilty to one charge of affray over the incident and was fined $1500 without conviction.