Officers were called to the scene by paramedics shortly after 4am.
The victim, believed to be in his 20s, was taken to hospital a critical condition.
Dudley Police confirmed that a section of the High Street will be closed on Sunday.
"A section of the High Street is closed today between Vicar Street and Stone Street while investigations continue, and buses are being diverted," a statement on social media said.
Investigating officers are urging anyone with CCTV, mobile or dash-cam footage to get in touch via Live Chat on the police website, quoting log 518 of 29 January.
West Midlands Police also told Express & Star that they don't believe this incident is linked to a murder investigation launched in Walsall on Saturday morning, after a man was killed following an attack by a group in the town centre.