During a sentencing at Sheffield Crown Court this afternoon, the court was told how in the run-up to the incident taking place on November 14, 2015, defendants Peter Gunning, 45, his son, Michael Gunning, 23, and their friend Ryan Graham, also 23, had been drinking in The Globe pub in Howard Street.
All three of the men admitted to also taking cocaine during the course of the evening, and Peter Gunning, of Sandstone Close, Wincobank, and Ryan Graham, of Hartopp Road, Heeley were also found in possession of the Class A drug when they were arrested following the incident.
Prosecuting, Geraldine Kelly, told the court that the victim in the case entered the pub with a few of his friends at around 10pm to use the toilet, and all headed straight there.
The three defendants went into the toilets a short time after the victim and his group of friends, and Ryan Graham started talking to the group.
Ms Kelly said: "Ryan said 'who are you then' and said 'do you support Sheffield Wednesday?'
"[The complainant] said: 'I support Manchester United' and Michael Gunning said: 'You will be alright then'."
Ms Kelly said one of the victim's friends told the police he had the impression the group were 'spoiling for a fight'.
She explained how violence broke out a short time later, and Peter Gunning punched another of the victim's friends in the mouth, causing a number of members of the group to leave the toilets.
This led to the victim being left alone with the three defendants, and Ms Kelly told the court how he recalled seeing Michael Gunning, also of Sandstone Close, Wincobank standing in front of him as Ryan Graham was to his left. Peter Gunning was seen holding the door by a member of the bar staff who tried to enter the toilets as the incident was taking place.
Ms Kelly said: "He felt pain to the back of his head and saw a glass out of the corner of his eye. He was then punched to the face by Michael Gunning, while Ryan Graham grabbed hold of him to prevent him from getting away.
"[The victim] fell to the floor."
After falling to the floor, Ms Kelly said the victim felt several blows to his body but could not see who was hitting him as things had become 'blurry'.
She said: "He [the victim] ran out, but was chased by Michael Gunning."
The police were called out to the scene a short time after the victim ran back into the pub to try and escape Michael Gunning, the court heard.
The victim was left with a number of injuries, and needed to have 35 stitches to the lacerations left where the glass struck him. He was also left with a bump to the back of his head and a haematoma to his forehead.
The court was told how the victim has four permanent scars, between 1 and 1.5 inches in size, as a result of the attack.
Michael Gunning pleaded guilty to wounding, and Peter Gunning and Ryan Graham pleaded guilty to wounding and possession of cocaine at an earlier hearing.
The court heard how Ryan Graham admitted to bringing the pint glass used in the attack into the toilet, but none of the three men said they had used it or that they had seen any of their co-accused using it.
Recorder Jeremy Barnett sentenced the three men to two years in prison, suspended for two years, for their involvement in the attack.
"This was an ugly incident," said Recorder Barnett, adding: "Peter Gunning you are a disgrace. A man of your age on a night out with your son, taking cocaine in a bar, drinking in this fashion - I can't even begin to think what you thought you were playing at. You are supposed to lead by example."
He continued: "Ryan Graham because of your..lack of judgement that night, because of what you had been taking, the lot of you in the toilet, an altercation broke out in the spur of the moment.
"You used a weapon, a glass. I think what happened was you jumped in to protect your friend, Michael Gunning, and you jumped in to protect your son Peter Gunning."
In addition to their two-year suspended sentence, Ryan Graham and Peter Gunning were sentenced to one month in prison, suspended for two years and to run concurrently, for possession of cocaine.
All three men were made the subject of a three-month curfew, and of a prohibition order which prevents them from entering city-centre pubs and clubs.
Peter Gunning was ordered to pay £750 in compensation to the victim of the attack, while Michael Gunning was ordered to pay £500 and Ryan Graham was ordered to pay £350.