A reconstruction of how an ice axe was driven into the skull of teenager Anthony Walker has been acted out at a murder trial.
Anthony Walker was attacked with an ice axe
Preston Crown Court also heard accounts of events from emergency service workers who tried to help the student after the attack in Huyton, Merseyside.
Anthony died from an axe blow of "quite considerable force", Home Office pathologist Dr Brian Rodgers said.
Michael Barton, 17, of Boundary Road, Huyton, denies murder.
His cousin Paul Taylor, 20, of Elizabeth Road, Huyton, has admitted murder.
The attack took place in McGoldrick Park after the teenager and his cousin, Marcus Binns, were racially abused as they waited for a bus outside the Huyton Park pub, the court was told.
At Mr Justice Leveson's request, Dr Rodgers demonstrated the blow with a replica axe and a court usher.
Dr Rodgers said the axe had smashed a 5.5cm-wide (2.1inches) hole into Anthony's skull, penetrating his brain.
Even the removal of the axe from Anthony's head required "considerable manipulation" by doctors, the court heard.
Dr Rodgers said it was likely Anthony was already on the ground when the axe hit his head.
"Once that blow was struck, I don't think he knew anything about it at all," he said.
Sgt Damian Peers found Anthony with the axe in his head by the entrance to the park. He said in a statement how the front of the ice pick was embedded in the front of his skull.
Anthony Walker was attacked near the entrance to McGoldrick Park
Paramedic Lawrence Sullivan said in his statement to the court that he had to load Anthony into the ambulance differently than normal to stop it causing further injury.
The court also heard how local resident Carol Roberts said she answered a loud knocking at the door to find Anthony's cousin pleading for help.
She said: "His eyes were wide open with terror and he was extremely agitated. I immediately knew something terrible had happened.
"He said 'They've got my cousin. They've got him in the bushes'."
The trial continues.