A woman has told murder jurors she tried to stop violence breaking out before she saw her soldier boyfriend attacking tragic Joseph Leech with a fence post in the street.
Nicole Leonard said she had warned Karl Pascoe to "leave it" before he lashed out at the stranger with the weapon when a row broke out as they made their way to her home in the early hours of December 23 2013.
Miss Leonard told Newcastle Crown Court she shouted "several" times in a bid to stop the violence but her "on-off partner" Pascoe, who was then a serving soldier, went on to attack.
Jurors have heard Mr Leech suffered a badly fractured skull and brain injuries in the assault near his home in Woodland Terrace, Washington and was "never the same again".
The 32-year-old, who became prone to having fits, went to bed at his parents' home for an afternoon nap on April 2 last year and "never woke up".
His lifeless body was found by his mother.
Pascoe, who was convicted of assault in the aftermath of the attack, is now accused of murder.
The 31-year-old, of Blackfell, Washington, denies the charge and is being tried by a jury.
Miss Leonard told jurors she and Pascoe had been on separate nights out but had met up to walk to her home together, which took them past Mr Leech's street.
She said she noticed Mr Leech, who was a stranger to them, walking past carrying a piece of wood and that Pasoe had said to him "whoever it is, he's not worth it" or something similar.
Miss Leonard said the stranger had replied with something like "here mate, I don't know who you are, leave me alone" and that an argument started between the men.
The court heard Miss Leonard had shouted repeatedly at Pascoe to "leave it", said she didn't want any trouble, and started to walk away when the row continued but then heard a "thud".
She added: "I guessed it was the fence post hitting one of them.
"I saw the male lying on the floor."
Miss Leonard said by then the fence post was in Pascoe's hand and she heard him tell the man on the ground "dont **** with me".
She told the court she then saw Pascoe raise up the fence post, holding it in both hands, and hit the man twice to the head with "a lot of force".
Miss Leonard added: "I knew he was hurt.
"He wasn't moving."
Miss Leonard, who gave her evidence in court from behind a screen, said Pascoe told her to "run" after the violence.
Pascoe denies murder.
The trial continues.