Police officers have issued an appeal for information following reports of a disturbance around 12.40pm on 1 February.
Emergency services attended the scene on Kilmacolm Road near Belville Street.
A 31-year-old man was taken to the Queen Elizabeth University Hospital where he remains in a stable condition, while a second man, aged 38, was taken to Inverclyde Royal Hospital and treated for a serious head injury.
The 38-year-old man was arrested in connection with the incident and released pending further enquiries.
Read more:
Detective Constable Kenny McLachlan said: “This area would have been very busy at the time of the incident so I am asking any members of the public who may have witnessed what happened to get in touch.
“Similarly, anyone in the local area with private CCTV or doorbell footage or drivers with dash-cam footage should also contact us, as you may have captured what happened.”
Anyone with information can contact police quoting incident 1302 of 1 February, or can anonymously contact Crimestoppers on 0800 555 111.
