A gardener accused of slashing his friend's throat said the man was just "unlucky" to have been caught by the knife.
Robert Morris accepts he killed Grant Flame during a violent drunken row but told a jury yesterday he lashed out with the craft knife as a warning.
Mr Flame, 44, a father-of-three from Worthing, was found dying in a hallway outside Morris' flat in Broadwater Road, Worthing, on January 24.
Morris, 41, denies murdering him.
He told Lewes Crown Court: "Grant was really strangling me and I couldn't judge the distance between where Grant's head was and my arm. It was a desperate act to make him back off."
The court heard the two men had spent the day drinking at Morris' flat with Marion Goldsmith, Mr Flame's partner and a former lover of Morris.
In the evening, Morris said Miss Goldsmith and Mr Flame started arguing about how they were going to get home.
Morris suggested she slept on his sofa but Mr Flame would have to leave.
Morris, who is profoundly deaf and was speaking through an interpreter, said Mr Flame attacked him.
Morris said he panicked and picked up the knife while he was being pushed back in his chair.
Morris said: "I just wanted him to let go and it just went across - it was just unlucky that it went across his throat."
The trial continues.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article