It was the early hours of a July 1990 morning when Brett Braddock and another man, never identified, broke into her Ballarat home and raped her.

They took turns, with one attacking her while the other held her down. They knew she had children in her home and they used them to threaten her.

Keep quiet or we'll kill your kids, the unidentified man told her, adding that he knew she had a teenage daughter.

For a period that must have been excruciatingly long for the woman, the unidentified man raped her. Braddock, then 26 and now 57, attacked next after pausing to check out a noise he heard outside the bedroom.

He was jailed on Wednesday, ordered by County Court Judge Patricia Riddell to serve 12 years and two months behind bars for "every woman's worst nightmare".

After getting away with the horrific attack for 28 years, he must now serve at least nine before he's eligible for parole.

The woman told her eldest daughter about what happened and called her mother for help, but she initially refused to tell the police what had happened to her.

"That was an act of maternal self-sacrifice," Judge Riddell said of the woman's fears for her children's lives.

A neighbour was called, and she called police.

DNA samples were taken and stored. A DNA profile was taken from the samples in 2012 but no match was found.

It wasn't until 2018 when the case was reviewed by the Sexual Crimes Squad's cold case unit that good old fashioned police work by the original investigator and fresh eyes identified Braddock as a suspect.

Although he had committed no other crimes, he had lived close to the woman at the time.

Officers knocked on his door and asked for a voluntary sample, and he agreed. The match came back - he was 100 billion times more likely to be the source of the DNA than anybody else.

Braddock denied knowing the woman, ever going to her house and raping her. He said he remembered police coming to his house to ask if he'd heard anything and that he found out later a woman had been raped.

He pleaded guilty to two charges of aggravated rape and one of burglary over the attack but Judge Riddell said she couldn't find he had any remorse because he claimed to have no memory of the attack.

Judge Riddell said the offending was in stark contrast to the rest of his life and noted family and friends described him as a loving family man and great friend.

"To say the uncovering of these offences have shocked those close to you would be an understatement," she said.

He still has the support of his wife, who he met long after the rape.

Braddock must undergo sex offender treatment while in custody.

Australian Associated Press