A man who violently attacked the eight-month-old daughter of his former partner has asked for a longer parole period for his inevitable time in prison.
The baby girl sustained bruising and injuries to her head and neck caused when the man grabbed and shook her at a western Sydney home in August 2021.
She was treated at Westmead Hospital, leading to an investigation by police and the arrest of the man, who cannot be named for legal reasons.
The 26-year-old faced sentencing at Parramatta District Court on Tuesday, when he was told by Judge Stephen Hanley that a prison sentence was guaranteed.
The western Sydney man pleaded guilty in June to one count of causing grievous bodily harm with intent.
Prosecutors dropped two remaining charges of intentionally choking a person without consent and doing an act intending to pervert the course of justice.
The latter charge relates to lies the man told to police after the assault.
Crown prosecutor Ben Page said the child sustained serious injuries in various ways, including through blunt force trauma, choking and the rapid shaking of the baby's head.
"Because of the age of the victim, it can't possibly be known at this point in time what her recovery will be," he told the court.
The assault was not just a single shake of the child and was "well above mid-range" in seriousness, Mr Page said.
The man, while expressing remorse for his actions, had also not explained why he attacked the child in the first place, Judge Hanley heard.
The 26-year-old sat silently with his head down in the dock wearing prison greens as the arguments unfolded in court.
Defence counsel Tahn O'Rourke denied there were multiple "mechanisms" for the injuries, saying that the assault was of short duration.
On the child's recovery, the barrister said there were positive signs, but long-term predictions could not be made because those currently taking care of the girl had missed two scheduled doctor appointments.
She argued for a longer time on parole, saying her client had no prior criminal history.
He had also been diagnosed with cognitive and mental health impairments, which led to the attack and which would make his time in prison more onerous, Ms O'Rourke said.
The man already required protection while on remand and Judge Hanley noted "jail justice" was often meted out by inmates to those convicted of child offences.
Ms O'Rourke said the man had positive chances of rehabilitation and that a longer, supervised time on parole would help him reintegrate into the community.
The judge will hand down his sentence on Monday.
