A man told a jury that he stabbed his friend to death by accident.
David Shannon, 28, denies murdering Spencer Borland, 41, by knifing him in the back in Campbell Place, East Kilbride.
Both men were in the living room of the home Mr Shannon shared with his partner when a row broke out on 14 May last year and they started struggling.
Mr Shannon told the High Court in Glasgow: "I didn't murder him. I'm not a murderer."
The jury heard the row broke out about 05:00.
Mr Shannon claimed that Mr Borland grabbed an ornamental knife which was on display and stabbed him on the hand.
He said he then grabbed the knife from Mr Borland, who then held him from behind.
The murder accused was asked by defence QC Gordon Jackson if he stabbed his friend while the pair were grappling with each other.
Mr Shannon replied: "Yes. I didn't think it had gone into him and then I saw the blood."
Mr Jackson asked him if he meant to kill Mr Borland.
Mr Shannon replied: "No I didn't intentionally stab Spencer. It was an accident. I'm not a violent person."
Prosecutor Mark McGuire accused Mr Shannon of attacking an unarmed man but Mr Shannon claimed the victim was trying to take the knife off him.
Asked why he didn't tell the 999 operator it was an accident, the accused replied: "I was panicking my friend was lying on the floor dying.
"I could barely speak. I was shaking like a leaf."
Mr Shannon denied that he had stabbed Mr Borland in retaliation for being stabbed on the hand by him.
The jury has heard that the wound to Mr Borland's back collapsed a lung and cut though a major blood vessel.
The trial before Lord Ericht continues.