A drunken man punched a house mate, knocking him backwards out of a door and into a garden fence.
Evaldas Devkis (19) then got into a tussle with the victim, Vaidas Kulboka, at a house they had shared for only three days in Bourne Road, Spalding.
Paul Wood, prosecuting, said Mr Kulboka got on top of Devkis, who calmed down and went back into the house.
He said Mr Kulboka had a cigarette outside, near a van, and Devkis appeared with a knife in his hand.
In a statement to police, Mr Kulboka said he saw the knife and thought “maybe he wants to slaughter me”.
Mr Wood said a woman house mate said Devkis carried the knife with the 15cm blade tucked up his sleeve and she took it from him with a degree of ease.
In his police statement, Devkis, was asked to describe his drunkenness on a scale of one to ten and said it was “nine”.
Devkis, now of Chervil Rise, Wolverhampton, was given a year-long community order with 200 hours unpaid work by Spalding magistrates on Thursday. He must also pay £85 costs and a £20 victim surcharge.
He pleaded guilty to assault by beating and possession of a knife, both on April 24.
Magistrates ordered forfeiture of the knife.
Solicitor Iona Hanrahan, mitigating, said: “The knife was removed by the female witness quite safely, without a struggle, and no one was injured.
“He doesn’t remember fetching the knife and he doesn’t know why he would have fetched a knife.”
Miss Hanrahan said Devkis accepted he threw the first punch and it led to a tussle.