A jury heard details of the last struggle of Joe Holland before his body was left in a locked bathroom with deep stab wounds to his chest.
Mr Holland, 25, also had a wound to the back of the head which a court heard "it was possible" had been caused as he was allegedly approached from behind and stabbed with a knife.
James Preston, 21, accepts inflicting the injuries which killed Mr Holland in the early hours of June 8 this year. Mr Holland was found in a "pool of blood" at the home of Preston's parents in Huyton House Road, Fincham, by police officers later that day.
Next to his body was a note written in blue highlighter, saying: "It was me or him", and a bloodstained knife with a bent blade. The jury of seven men and five women has heard the incident followed a ketamine fuelled night out with a group of friends.
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Preston is on trial at Liverpool Crown Court after pleading not guilty to Mr Holland's murder and an alternative count of manslaughter. The jury has heard he will claim he acted in self-defence when he stabbed Mr Holland, penetrating his lung, heart and liver.
Today the defence called pathologist Dr Anthony Bleetman. The jury heard the court had allowed Dr Bleetman to give evidence during the prosecution case as he was unavailable next week.
Dr Bleetman agreed that Mr Holland's body had been found with 11 incised wounds, including two "particularly serious" deep wounds to the left side of the chest.
The jury heard Dr Bleetman had been asked by the defence to consider whether any injuries to Mr Holland could have been caused in a scenario where he was holding the knife himself. The jury heard he was provided with an extract of Preston's defence statement, giving his account of how the fatal incident occurred.
That statement said: "Believing that Joseph Holland was trying to kill him, James Preston got a grip on the hand in which Joseph Holland held the knife. In the struggle to gain possession of the knife, the knife was time and again forced against the person of Mr Holland and some of the injuries to Mr Holland would have been gained in this struggle, in which both men came against kitchen furniture
"At some stage the knife was dropped. Mr Preston picked it up and swung the knife at Mr Holland, who fell backwards against kitchen furniture. It was that action that ended the struggle. It became clear that Mr Holland was dead."
Dr Bleetman was asked about the injuries suffered by Mr Holland, which included a stab wound to the upper left side of his chest which severed his third rib, passed through the upper part of his lung and penetrated the left ventricle of his heart.
The court heard injury would have rapidly resulted in collapse. There was also a second serious injury, a stab wound to the lower left side of his chest which also damaged his lung, passed through his diaphragm and damaged his liver.
He told the jury it was "extremely unlikely" that Mr Holland was holding the knife when those injuries were inflicted.
Referring to the first wound, he said: "The force required to plunge a knife into the body and sever a rib, and continue into the body after severing a rib, would have required a very significant large amount of force."
Nick Johnson, KC, defending Preston, asked: "Is that force all necessarily coming from the person with the knife?".
Dr Bleetman said: "It could be a summation of forces from both parties. If the person is applying the knife, and should the victim of that wound be running towards the person holding that knife, the forces could be added to produce the ultimate force that was actually transferred during that strike."
Mark Ford, KC, prosecuting, cross examined Dr Bleetman on his findings, referring to a number of cuts to Mr Holland's left hand. He suggested: "He could have received those wounds as he was trying to defend himself from an attack with a knife?"
Dr Bleetman said: "He could have done yes", further agreeing that those injuries could have been "a parry or an attempt to grab the blade". Mr Ford said: "Either way self defence?". Dr Bleetman said: "Yes."
Mr Ford turned to the injury on the back of Mr Holland's head, described as a "through and through" wound where the knife had penetrated the skin and re-emerged again. He said: "Does it therefore follow it’s possible this stab wound was caused when Joe Holland had his back to his assailant?"
Dr Bleetman said: "It's possible, or the wound could have could have from the side or an oblique angle."
Mr Ford said: "Yes. One real possibility is that he had his back to the defendant, who came up behind him and used the knife to stab him in the back of the head?"
Dr Bleetman said: "That is possible."
The trial continues.
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