The incident left Hells Angel Corey "Tiny" McInnes in hospital nursing a minor stab wound and a 27-year-old man severely beaten in a nearby back lane.
Neither spoke to police and any witnesses to the stabbing also declined to give statements.
Sources said it began when a second Hells Angel, Darren Hunter, and the 27-year-old man got into an altercation at NV nightclub.
The man's friend, local gang associate Mario Adamo, intervened as did McInnes -- with McInnes getting the worst of it.
Adamo and his friend quickly ran out of the bar. Less than a block away Hells Angels associates caught up to the man in a back lane and began beating him.
People in the area called police about what was happening. Officers soon found the beating victim lying behind an apartment block.
Police and other sources say Adamo, 33, escaped and hasn't been seen since.
"He's lying low," one said.
Friends took McInnes to Victoria General Hospital for treatment.
This isn't this first time Adamo has had a run-in with the bikers.
Seven years ago he was beaten with a baseball bat at the gang's old clubhouse in Elmwood. Adamo spent several days in hospital recovering from a fractured skull.
Hells Angels members Shane Kirton and Rod Sweeney were later sentenced to eight months in jail.