A man stabbed a fellow party-goer to death because he was "seeing red" at having been placed in a headlock by him, a court heard today.
A fight broke out when Daniel Tulloch put his leg out to stop Tarirai Munjanja going down a flight of stairs during the party in Slough, Berkshire.
Tulloch, 36, who had previously lived at the house, then taunted Mr Munjanja by saying: "You think you're a rude boy," and a scuffle ensued, Reading Crown Court was told.
Mr Munjanja, 23, placed the other man in a headlock to make him calm down, prosecutor Ian Acheson said.
But when Tulloch was released, he went into the back garden of the property to retrieve a knife, it is claimed.
He went to the front garden, where Mr Munjanja had gone to get food from a barbecue taking place there.
Tulloch saw Mr Munjanja go to an area of the garden used as a makeshift toilet and shouted abuse before stabbing him once in the stomach, the trial heard.
The blow proved fatal, severing a major artery. Mr Munjanja screamed and then shouted to other guests, using a slang term for being stabbed: "I've been stabbed. The mother duked me."
Mr Acheson told the jury: "Whether he was about to relieve himself or was just standing there, it appears from the evidence that Mr Tulloch, having started verbal hostilities, approached Mr Munjanja and struck him once to the stomach.
"It was just once, one blow. The effect of that one blow was immediately apparent.
"Mr Tulloch ran straight away down the pathway towards the back garden, aware of a park that is over the rear fence."
Mr Munjanja collapsed and died an hour and 15 minutes later in hospital of massive internal bleeding.
Mr Acheson said: "The prosecution case is that Mr Tulloch, seeing red at being shown up by being put in a headlock by Mr Munjanja, decided to seek retribution, went and got a knife and started a second episode of violence on very different terms by sinking a knife into his stomach."
Tulloch, of Bradley Road, Slough, denies murder, claiming the knife was Mr Munjanja's and that he was acting in self defence on the night of August 29 last year.
The trial is expected to last for a week.