A man who attacked his victim outside Melbourne's Northcote Social Club and left him with serious head injuries has been sentenced to nine months in prison. 

According to Herald Sun, Robert Joseph pleaded guilty in County Court to the attack that occurred on 21 February 2015, after he followed the victim outside the venue and knocked him to the ground by punching him in the head, resulting in bleeding on the brain.

The victim reportedly suffered facial palsy, dizziness and psychological issues following the attack and was also unable to work for some time.

"(The victim's) body went limp and he fell into the road," Judge Paul Grant said.

"You walked away (and) did not assist him in any way."

The defence argued that Joseph had been struggling following a relationship breakdown that year and had also been drinking heavily.

Grant took into account the fact that Joseph was abused as a child by his own alcoholic father and that he was "not normally violent" and showed "genuine remorse".

Grant added that Joseph is a "proud Aboriginal man" and noted that he is actively involved in the lives of his two children.

Joseph's nine-month prison sentence is to be followed by a community corrections order of 21 months.