A TEENAGER who nearly killed a man by stabbing him in an unprovoked attack in Old Town has been jailed for five years and four months.

Kelam Smith, 18, went back to his room in The Foyer on Bath Road to get a knife after his victim had stepped in to try and calm him as he rowed with his girlfriend.

And if a passing police patrol had not spotted James Corns slumped over a taxi at the top of Victoria Road he may have died as he had lost more than a pint of blood.

The 26-year-old also suffered a punctured lung and lacerated spleen in the attack, Swindon Crown Court was told.

Matthew Scott, prosecuting, said Mr Corns had been out drinking in Old Town and was on his way home shortly after 3.30am on Sunday November 6, 2016.

"He had seen an argument between a man and woman. He said something to try and make the man calm down and walked off," he said.

"While he was walking off down the road he felt something hit him in his back. He put his hand back and it was wet: it was wet with his blood."

Mr Scott said a passing police armed response unit came up to the Bath Road junction and saw the lifeless body slumped over a car.

When they approached the officers realised he was seriously injured and applied emergency first aid before he was rushed to hospital.

At about 8.30am Smith approached the police cordon which had been set up and when he was told it was crime scene, he replied it was his crime scene.

He also told officers he stabbed a man because he was wearing black, and next time it would be someone in green or red.

After he was arrested he was taken to the police station and Mr Scott said he appeared to be forensically aware as he tried to shower in a cell to remove evidence.

Meanwhile his girlfriend cleaned his clothes and the knife, which she then dumped down a drain in the Town Gardens.

When he was questioned he denied the stabbing and initially pleaded not guilty, only later changing his plea last summer.

As a result of the attack Mr Scott said the victim, a keen rugby player, could no longer take part in the sport because of his injuries which still affect 14 months on.

He also had a long period off work and could also not play with his young child because of the wound.

Smith, of The Foyer, pleaded guilty to grievous bodily harm with intent and possessing a bladed article.

Adam Williams, defending, said his client was still 17 at the time and had an undiagnosed and untreated mental heath disorder at the time of the incident.

He said just days before he seen psychiatric services and had also been assessed by medics while on remand and treated.

Since being inside he said he hoped to train as an engineer so he could get work when he is finally released.

Jailing him Judge Tim Mousley QC said: "I am satisfied even on that basis there was a degree of premeditation in what you did.

"When you came upon him you stabbed him from the back: it was completely unprovoked. Passing police officers found him before he had collapsed completely.

"The injuries could have been much more serious: I am satisfied that they were life threatening.

"Had the police not been passing at that moment one can only speculate as to what might have happened."

Lauren Wyatt, 19, of Bright Street, was put on a suspended sentence after she pleaded guilty to perverting the course of justice.