Convicted rapist Anthony Sampieri has been sentenced to life in prison for raping a seven-year-old girl in the bathroom of a dance studio in Sydney’s south.

The paedophile will die in jail after Acting Judge Paul Conlon did not set a non-parole period.

The 56 year old pleaded guilty to 10 charges related to the attack including three counts of sexual intercourse with a child under 10.

Sampieri - who was on parole at the time for raping an elderly woman in 2012 - grabbed the girl as she entered the bathroom of the dance studio, and later dragged her into the men’s toilet.

He punched and bound her before subjecting her to depraved acts for more than 40 minutes.

During sentencing, Conlon said Sampieri “had a callous disregard” for the victim and that “there will be lifelong consequences for her to deal with” including the effects of long-lasting trauma that will impact her when “entering an office or public toilet ... or even entering a toilet in her own home.”

“It is a parent’s worst nightmare,” he said.

The court also heard further sickening detail on what he did to the terrified child.

Conlon said Sampieri “grabbed the victim and pushed her into the cubicle and locked the cubicle door”, he then told her to perform fellatio and when she refused he “punched her to her left cheek”.

When she was found by her mother and diesel mechanic Nick Gilio, who has since been hailed a hero, the girl was on the ground of the toilet, tied up and gagged.

The court heard that she immediately “burst into tears and was in distress”.

She hadn’t been able to call out because her mouth was full of toilet paper.

Rapist’s apology

During a sentencing hearing in the NSW District Court last Friday, Sampieri apologised for his sex crimes, referring to the “insanity” of his drug addiction.

“I am so, so sorry I did what I did,” he said in an apology directed to the then-seven-year-old victim.

“Using crystal meth, I believe that led me to what I did. I am sorry I let you down by using crystal meth again.”

He also apologised to Gilio who was among several worried adults looking for the missing girl when he found the victim tied up.

Last November, Gilio told the NSW District Court he still has flashbacks to the moment he caught the paedophile trying to leave the bathroom and that he wishes him a life of “pain, darkness and misery”.

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Sampieri reached for a knife when confronted by Gilio and began swinging at him and the victim’s mother who had also entered the bathroom.

He was overcome only after the bleeding mechanic grabbed him in a headlock as dentist Jeffrey Stack burst through the door and punched the paedophile twice in the face.

“There is no forgiveness or rehabilitation for what you have done. For the consequences of your actions, you must suffer,” Gilio said at the time.

Sampieri last Friday said he felt “really, really bad” about what he had done.

“I feel if I could change it I would,” he said.

- With AAP