A TEENAGER left a boy with a life-changing brain injury after he was brutally attacked outside a McDonald’s following a falling out over a girl.

The 16-year-old from Newport seriously assaulted another boy, also aged 16, in the Rogerstone area of the city on a Friday night last October.

The defendant stamped on his victim’s head when he was defenceless on the ground after he had been punched, kicked and knocked to the floor.

Witnesses described how he was “smirking” and “smiling and laughing” after leaving the other boy unconscious.

The complainant was rushed to Cardiff’s University Hospital of Wales (UHW) and underwent emergency surgery after suffering a bleed on the brain.

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Both boys had initially traded blows before the defendant stamped on his head on at least two occasions when he got the better of the fight.

The parties cannot be named for legal reasons – their identities have to be protected because of their ages.

Jason Howells, prosecuting, played footage of the attack which was captured on CCTV at the McDonald’s.

The defendant’s assault was alcohol-fuelled, with Cardiff Crown Court hearing how he had downed a bottle of wine and cans of alcohol that evening.

He described himself to the police as "eight out of 10 drunk".

The complainant was transferred to the UHW after initially being treated at the Grange University Hospital in Cwmbran.

Mr Howells read out the victim impact statement to the court.

The boy said: “The actions of the defendant have changed my life and how I planned to grow up.

“I don’t want to see him again – he has changed my life beyond all recognition.

“There was no real reason for him to have done this to me.”

The defendant pleaded guilty to causing grievous bodily harm with intent.

He had no previous convictions.

Joshua Scouller representing the teenager said his client’s fateful decision to stamp on his victim was made in a “split second”.

His barrister added: “This was a fast moving and fluid incident.

“The defendant expresses remorse and sadness to his victim.

“There is genuine empathy.”

Judge Eugene Egan told the boy: “What did you did was very serious.

“Custody is the only sentence I can give you.

“This was a grave crime.

“You caused your victim very serious injury and he was totally defenceless – he was at your mercy.

“His life may have been in jeopardy but I can’t be certain about that.”

He described the attack as “cowardly”.

The defendant was sentenced to 29 months youth custody.

He will have to serve half that term before being released.

The teenager was also made the subject of a 10-year restraining order not to contact his victim.

The defendant has to pay a £41 surcharge following his release.