Judge Joe Gullaci jailed 20-year-old Alfer Azzopardi who bashed Mukesh Hairkerwal with serious blows with a baseball bat, for 18-and-a-half years with a minimum of 13-and-a-half years, media reports said.
Former chief of Australian Medical Association Haikerwal was walking through a park in the bayside suburb of Williamstown on Sep 27, 2008 when he was set upon and bashed by the men.
Another co-accused Michael Baltatzis, who together with Azzopardi was jailed for 16-and-a-half years and must serve 10-and-a-half years before being eligible for parole.
A third man, Sean Gabriel was jailed for nine years and nine months with a minimum of six years, report said.
Announcing the sentences, Judge Gullaci dubbed the attacks as cowardly and despicable.
"Each of the victims was selected at random, but each had a common feature, that is they were vulnerable and alone and in parks or (other) public places," he was quoted by news agency as saying.
Welcoming the judgement, Sydney based cardiologist Yadu Singh said "It is a very good move and will send a strong message to such criminals that were attacking people for no reason.