Businessman Anthony Lyons is to go back behind bars after a court ruled a six-month prison sentence for a violent sex attack was too lenient.
Family and friends of the convicted sex offender's victim hugged when the Court of Criminal Appeal delivered their ruling.
She was not in court as the three judges upheld an appeal by the Director of Public Prosecution (DPP) against the length of the sentence on grounds the trial judge had been too lenient.
Mr Justice John L Murray said given the gravity of the offence the mitigating factors could not justify the custodial part of the sentence.
The case will be listed again next week when submissions will be made on an appropriate jail term.
Lyons was sentenced to six years by Judge Desmond Hogan in July 2012 for attacking the then 27-year-old woman in the early hours of the morning of October 3, 2010.
But the judge sparked outrage when he controversially suspended five and a half years of the jail term and ordered him to pay his victim 75,000 euro in compensation.
Lyons admitted the attack - in which the victim was rugby tackled to the ground and violently physically and sexually assaulted - but claimed he was overcome with an "irresistible urge" due to a combination of alcohol, cholesterol medicine and cough syrup.
The former aviation boss from Griffith Avenue in Dublin was convicted by a jury after pleading not guilty at Dublin Circuit Criminal Court to the sexual assault.
Defence barrister Patrick Gageby SC said Lyons was the most unlikely person to have committed an offence like this.
"He was a man who had never been in trouble of any kind," he added.
"He was a man who was quite able to ask of gardai was there any suggestion of suspicion against him in relation to any other matter.
"He is a man who appears to have committed this criminal offence just touching on his 50th year, happily married, hard working and incredibly well thought of by all who knew him.
"It was unusual first offence and for sure his last offence."
Mr Justice Murray told the barrister it had been a most disturbing offence for the victim.
"That it was his first offence or not did not make any difference to her in the end," he added.
Counsel for the DPP, Caroline Biggs SC, told the appeal court the six-month custodial sentence did not reflect the gravity of the offence, the impact on the victim and the impact on society.
She argued undue weight and a disproportionate reliance was given to mitigating factors, in particular the compensation, and that the trial judge erred in principal when sentencing despite accepting it was at the most serious end of the scale.
"He failed to have sufficient regard to the gravity of the offence, the impact on victim, the impact on society... and general deterrents were fundamentally ignored," she added.
Elsewhere Ms Biggs claimed the accused showed no contrition by pleading not guilty.
Dressed in a dark blue suit and red tie, Lyons - a former boss in Dublin-based Santos Dumont aviation firm - was supported by family members in court for the hearing.
He showed no emotion when the ruling was delivered and left the courts complex without making a statement.
Mr Gageby said there had not been any evidence that the judge weighed so much on compensation while sentencing.
He maintained Lyons could not submit a defence of involuntary intoxication without denying the charge, but claimed his client had offered to accept the victim's statement as evidence in court sparing her taking the witness stand.
"I utterly accept the fact Mr Lyons pleaded not guilty," said Mr Gageby.
"There's no other method for determining this difficult area of involuntary intoxication.
"If there was another way we would have gladly embraced it."