The man, who The Courier cannot name for legal reasons, received a two year and nine month sentence, but two years and two months will be suspended for three years.

Judge Damian Murphy, in the County Court at Ballarat, said it was a serious and complex case, with the man using the child "for (his) own sexual gratification".

The man pleaded guilty to six charges, including sexual penetration of a child under 16 years, and indecent acts near or with a child.

The court was told the offending began when the man was 17, and living with the child, who was then aged about 10.

The offending began with games of truth or dare, and escalated over a period of years - the charges state the offending only ended when the man left home to move to Western Australia when he was almost 22.

Victim impact statements from the victim and his mother show the offending had a horrific effect, causing the breakup of their family - the victim's mother said she felt she had "failed as a parent".

The victim said in his statement he had turned to a life of drugs and still had issues trusting others in the years since.

The offending came to light when the victim mentioned the abuse to his family, and the man, then married in Western Australia, made admissions to police.

Judge Murphy said his cooperation with police and early plea of guilty were mitigating circumstances in his sentencing.

The complexity was the man's age at the time of the offending - two of the charges related to offending over a four year period, between the ages of 17 and 22, though without specific timing for those incidents.

There are different thresholds for moral culpability for younger sexual offenders, Judge Murphy said.

The man's defence noted his troubled upbringing and poor maturity for his age as contributing factors for his offending - the victim's abuse began when he was the same age as the accused was when he was abused.

The delay in getting the case before the court because of COVID was also noted, with Judge Murphy stating it would have "hung over your head".

The man was sentenced as a serious sexual offender - had he pleaded not guilty, he would have been sentenced to four years and six months prison, with a non-parole period of two years and three months.

He had flown from his home in Western Australia for the sentencing, with the court noting he retained the support of his wife and mother-in-law.

He will not be placed on the sexual offenders registry.

Affected by this story? There is help available.

You can phone the Ballarat Centre Against Sexual Assault, in Sebastopol, on 5320 3933, or free-call the crisis care line 24 hours on 1800 806 292.

Or phone Lifeline on 13 11 14, the Blue Knot Foundation on 1300 657 380, or Relationships Australia on 1300 364 277.

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