A 47-year-old man was stabbed in the chest in Inverclyde in the early hours of Boxing Day, police have said.
The man was found seriously injured in King Street, Port Glasgow, at about 0030 GMT on Sunday.
Police said the man, who had earlier been in the nearby Comet Bar, was treated in hospital where he was said to be in a stable condition.
Officers were treating the incident as attempted murder. They said they had no description of the suspect.
Det Sgt Nigel Gilmour said: "The investigation is at an early stage and we are working to establish a motive for this attack.
"Police are currently carrying out enquiries in the local area to glean more information and we are checking local CCTV to try and identify those involved."