Raymond Strachan, 24, told police he left his house after witnessing the attack at Edinburgh’s Restalrig Circus on September 20, 2014.
Mr Strachan yesterday told the High Court he saw a number of “very vicious” kicks to the man being attacked. He said when he approached the victim he saw a garden fork lying on him, and the handle of a knife under his head. His face was covered in blood.
When detectives came to ask Mr Strachan to describe the assault, he told them: “They were forceful kicks – like somebody kicking a football as hard as they could.”
Mr Strachan was giving evidence on the fourth day of the trial of Gary Sim, 21, James Watson, 27, and Paul Watson, 29.
The three men deny murdering Thomas Lamb, 46, at Restalrig Circus last year.
Mr Strachan, who has vision problems, told the court that from his home on the night of the alleged murder he heard shouting and laughing.
He told the court that when he went to the window, he saw a man lying on the ground being struck repeatedly.
Mr Strachan decided to go out to investigate. By the time he got to the man’s side, he saw a number of men running away from the scene.
After moving the garden fork, he noticed the knife.
Mr Strachan told prosecution advocate Tim Niven Smith that the man’s face was covered in blood.
He added: “His head was on the handle of the knife.”
When Mr Niven Smith asked him how he felt at seeing this, Mr Strachan said: “I was just shocked.”
Prosecutors allege that on September 19 or September 20, 2014, at the Tor Public house in the Capital’s Restalrig Road, Gary Sim assaulted Mr Lamb.
The second charge alleges that on September 20, 2014, at Restalrig Circus, Sim and the two Watsons repeatedly struck Mr Lamb on the head and body.
Prosecutors claim that the three men then repeatedly kicked and jumped on Mr Lamb’s head and body before repeatedly striking him “with a garden fork, knife or other similar sharply pointed or bladed instrument”.
It is then claimed that Mr Lamb sustained multiple stab wounds and that the three men murdered him.
The trial, before judge Lord McEwan, continues.