Police were called to the scene in Wren Road, Greenock, Inverclyde, at around 7.10pm yesterday.
The dead man has been named as 23-year-old Jamie Walsh.
Following a post-mortem examination his death is now being treated as murder.
It is understood that police are following a positive line of inquiry.
The force appealed for information.
Detective Inspector Margaret Ann May said: “A young man has lost his life in a senseless attack and it’s imperative we trace the person responsible.
“I would appeal to anyone who may have witnessed this incident or who has any knowledge or information to contact us as a matter of urgency.
“We are currently piecing together what has happened and your information could prove vital to that puzzle so please do get in touch.”
Officers have been carrying out door-to-door enquiries and are in the process of reviewing CCTV images as they try to establish what happened.