But Canterbury Crown Court heard that although he immediately apologised, when neighbours burst in having been alerted by Ms Robbins screams, he told them they were "just playing" and it was an accident.

His lies continued following his arrest by denying he had been with his girlfriend that day and that she had concocted details of the assault.

Then, even after he had admitted his guilt in court almost four years later, he falsely accused her of having attacked him with a knife.

Now, the dad is starting a prison sentence after a judge dismissed his allegations and heard how Ms Robbins's injury was so serious she needed surgery that has left her permanently scarred.

Her ongoing fear was also said to have forced her to move with her daughter out of the county, with her ordeal exacerbating her anxiety and Tourette syndrome symptoms.

But despite being assessed as high risk, it is likely that Prendergast could be back on the streets in a matter of weeks.

The court heard last Friday that he and Ms Robbins had known each other since 2014 and were in an on-off relationship from January 2021.

It was on the morning of October 6 that year, having dropped her daughter at school, that she returned home and a row erupted between the couple, said prosecutor Clarissa Rodio.

Prendergast, who had stayed at the flat overnight, told the mum she had to "change her ways in a week" or he would leave.

He then greeted her response of "Don't give me a week. Leave now" with anger and refused to go as Ms Robbins pushed him towards the door.

Then, having gone into the bedroom, Prendergast told Ms Robbins "I'll leave when I want to leave" before pinning her down on the bed, straddling her and holding her arms above her head.

Described as being "very afraid", she tried to kick and bite him in desperation and it was once free of his clutches and while shouting at him to "Get out" that he punched her.

With her being clearly injured as a result, Prendergast said he was sorry. It was at that point two neighbours came to Ms Robbins' rescue.

"They opened the flat door, ran into the bedroom and shouted at the defendant to leave," said Ms Rodio.

"He said 'It was an accident. We were just playing', to which Ms Robbins said he was lying and he left."

Ms Robbins later attended Buckland Hospital where she was treated for a broken arm, and two weeks later had to undergo surgery to fix a metal plate due to the complexity of the break.

The couple stayed in touch, however, and Prendergast told her he would look after her while she was recovering, only to leave the morning after the operation following another argument.

Describing Ms Robbins's reaction to him leaving her, the prosecutor said: "She suffered an anxiety attack, cut off her cast, took a picture of the scar on her arm and sent it to the defendant.

"He expressed no remorse and didn't deny causing the injury."

She suffered an anxiety attack, cut off her cast, took a picture of the scar on her arm and sent it to the defendant...

The matter was reported to police the following week and Prendergast was arrested on December 6, 2021, having initially run away from officers when they pulled his car over.

When interviewed, he gave a prepared statement denying the assault, claiming he did not see the victim that day.

Prendergast, of Mayers Road, maintained his innocence in a legal document known as a defence case statement filed to the court and did not plead guilty to inflicting grievous bodily harm until the day of trial in April this year.

Charges of sending a malicious communication and criminal damage of Ms Robbins's phone were left on file.

In her victim impact statement summarised to the court, Ms Robbins was said to have "made clear" the pain and distress she suffered, how she has struggled to recover, and that the "giant" scar she bears is a constant reminder of the attack.

"I am a shadow of my former self because of what Liam has put me through," she wrote.

It was accepted by the prosecution that although Prendergast's action that day had been "impulsive, spontaneous and short-lived", the injury was grave and had caused permanent scarring.

Silas Lee, defending, urged the court to impose a suspended sentence order so that his client's "attitudes towards women and partners" could be addressed with the support of the probation service.

"He is exactly the type of offender that needs this kind of intervention," he told the court.

The lawyer also submitted that the stringent bail conditions imposed on Prendergast since the offence had been "a burden", and that the delay in the case reaching court should also be considered.

Highlighting that Prendergast also had a job offer working on a fishing trawler, Mr Lee added: "There must be serious punishment for this offence and the defendant has said he will comply with any conditions, whether unpaid work or a further curfew.

"He will do everything he can to stay out of prison."

However, on sentencing, Recorder John Bate-Williams made it clear that despite all that had been said on his behalf, immediate custody was the only option.

He also dismissed Prendergast's claims to the author of the probation report of having to defend himself against a "fevered knife attack" by his victim as having "no belief or credence".

Furthermore, he said the report and its findings made "worrying" reading.

Jailing Prendergast for 16 months, the judge explained: "You are considered to be high risk of reoffending and high risk of causing serious harm to partners, ex-partners, family members, future partners and even to your own children.

"Given those risks, the conclusion (by the report author) is that you are not safe to be managed in the community.

"This was a really nasty, violent assault on Sophie Robbins from which she is yet to recover and which has left a very obvious, nasty and permanent scar, as well as other consequences.

"I have come to the clear view that given the risk and danger you present to others, and the nature and context of the domestic assault on your part, appropriate punishment can only be achieved by immediate custody."

But in indicating that the actual time spent behind bars would be relatively short, given that Prendergast will only have to serve half that jail term less 147 days spent on a qualifying tagged curfew, Recorder Bate-Williams expressed his hope that he would be able to "take advantage" of any opportunity given to him in addressing his "anger management and intimate relationships" problems.

You are considered to be high risk of reoffending and high risk of causing serious harm to partners, ex-partners, family members, future partners and even to your own children...

Prendergast, who has a total of seven convictions for 14 offences - many committed after the attack on Ms Robbins - also admitted failing to surrender to bail.

The court heard he had been due to be sentenced on Thursday of last week but failed to turn up, resulting in a warrant being issued for his arrest.

Police therefore attended his home where they were greeted by Prendergast in a state of undress.

Offering an apology to the court and explaining the defendant had not been seeking to "run away or evade justice", Mr Lee said: "He was up all night before the hearing.

"He was worried about it and very anxious about the prospect of being sent to prison.

"Then, having eventually fallen asleep, he overslept and when police attended he answered the door wearing very little clothing, having just come from bed."

But although this prompted the judge to ask whether Prendergast had an alarm clock, no separate penalty was imposed for the bail offence.