Detectives say the man is one of at least 5 pub goers who were attacked at the Bretherton Arms in Eaves Lane shortly after 1am on Sunday (September 13).
Police were called to the pub after two men reported being hit with a baton-type weapon by a group of three men in dark clothing.
The victims, aged 22 and 40, were taken to hospital with 'significant injuries' to their heads and faces. Detectives said the injuries are not life-threatening, but the 40-year-old has suffered a serious eye injury which has required surgery to save his vision.
Officers have since spoken to a further three men who say they were also violently assaulted.
Lancashire Police said no arrests have been made but enquiries are on-going.
Detective Constable Laura Thornley, of South CID, said: "This was a really serious assault which has left a number of men with some significant injuries.
"At this time it is believed that three male suspects are responsible for the assault. All of whom are described as wearing dark clothing.
"I would appeal to anyone who saw the incident or who has any information to get in touch.
“I know there were a number of people who filmed the incident on mobile phones and I am especially keen to hear from anyone who may have footage and has not yet spoken to police."
Anyone with information should contact police on 101 quoting log number 97 of September 13 or independent charity Crimestoppers on 0800 555 111.