Police were called to the scene in Butts Road at around 6.15am on Sunday to reports of disorder.
A man in his 50s was taken to hospital with facial and chest injuries.
A 37-year-old was also taken to hospital with minor stab wounds – and later arrested on suspicion of assault. He has since been bailed.
West Midlands Police officers are continuing to appeal for information following the incident.
A spokesman said: "We are investigating following disorder in Butts Road, Wolverhampton, around 6.15am on Sunday.
"A man in his 50s remains in hospital with facial and chest injuries although they're not life-threatening. He will be spoken to around what happened in due course.
"A 37-year-old man who was taken to hospital with minor stab wounds was later arrested on suspicion of assault. He has been bailed pending further enquiries.
"Our enquiries are continuing and anyone with information is asked to contact us."
A West Midlands Ambulance Service spokesman said: "A man has suffered serious injuries after being attacked in the Penn area of Wolverhampton. An ambulance, a paramedic officer and the Midlands Air Ambulance Critical Care Car were sent to the scene after a number of 999 calls at around 6.20am on Sunday morning.
"The man was treated at the scene for multiple serious injuries before being taken on blue lights to hospital."
Anyone with information can call West Midlands Police on 101, quoting log number 666 of April 25.
Alternatively, contact Crimestoppers anonymously on 0800 555111 or at crimestoppers-uk.org