THE teenager who killed Adam Rogers is today starting three-and-a-half years detention — a sentence backed by the victim's family.

William Kingsley Upton, a 17-year-old from Rishton, was sentenced for the manslaughter of the 24-year-old Padiham Ladies' football coach from Blackburn.

Mr Rogers was felled with a single punch in Blackburn town centre last July and banged his head on the pavement. He died the next day after suffering brain injuries.

Despite claiming self-defence and putting Adam Rogers' grieving family through the ordeal of a trial, parents Pat and Dave Rogers said they hoped their son's killer could 'change for the better'.

Their comments came after the twice-adjourned sentencing of Upton, who had lost his temper and lashed out at 'peacemaker' Adam in the early hours of July 5, 2009 following a row between two groups.

The judge said Upton was cowardly for fleeing the scene and then boasting about the attack on the internet.

Judge Stuart Baker also said it was another of the 'seriously worrying' cases brought before him in which a young person had drunk until 'grossly uninhibited' and used violence 'as a first resort'.

Holding his wife Pat's hand outside court, Dave Rogers said: “For us it has never been about the length of the sentence, it's more to do with what happens afterwards.

“It is a tragedy for both families. We can only hope this experience he is going to have will change him for the better and he is able to deal with his problems.

“We heard enough in court to suggest he has already started that process.

“On Adam's behalf, he wouldn't have wanted more than that."

The Rogers family also warned about the dangerous of 'gratuitous violence as an acceptable part of a night out'.

“One punch can often be one punch too many", Dave Rogers said.

Sentencing Upton to four years detention minus 187 days spent in custody and on curfew, Judge Baker said: “This was a very grave crime which brought to an abrupt end the life of a very responsible, sensible and decent young man who was enjoying a night out.

“It has caused incalculable and inconsolable grief to his family and friends.

“No punishment which I can impose can undo any of the damage which you have done."

Judge Baker slammed Upton's 'provocative' behaviour throughout the incident which ended in Adam Roger's death.

“You had consumed excessive alcohol which of course at the time, aged 16, you should not have been doing. This is one of a seriously worrying number of incidents in which young people drink until they are grossly uninhibited and react to any perceived grievance by using violence as a first resort.”

Judge Baker added that Upton's conduct after the punch had landed was 'cowardly and uncaring', saying it was 'inconceivable' that he had not heard the 'appalling impact' of Adam's head hitting the pavement.

“You fled the scene as fast as you could not knowing or caring what you had done."

He also criticised Upton for boasting about the punch on social networking site Facebook, in which he referred to Adam's fall with one word: 'Timber'.

In mitigation, defence barrister Mark Stuart said there were ' no winners' in the case and that Upton, a 'bright and talented' young man, had already become a mentor while in custody.

After the case, Detective Superintendent Neil Hunter, said “This is a tragic case where a young man has lost his life and no sentence will ever be enough for the pain Adam’s family have suffered due to the complete stupidity and recklessness of this drunken teenager.

“I would like to think that this will serve as a strong warning to those who choose to behave in this reprehensible and shameful manner; but remain to be convinced. It should be a sobering reminder that if you choose this course of action, invariably, you will be sent to prison.

“Adam’s death was entirely preventable and has ruined the lives of so many people, not least of which are the Roger’s family who have had their son taken away from them in the prime of his life.

“Our thoughts remain with the family today who have throughout this investigation, and especially during the trial, conducted themselves with tremendous dignity. I hope this sentence will help them cope in some small way with their tragic loss although nothing anyone can do will ever bring Adam back."