Barry Kirkham, 47, was punched once in the face and fell to the ground during the fight outside Zeko’s takeaway on Park Road, St Annes, on July 22 last year.
While he was on the ground and unconscious he choked on his own vomit, causing his death, an inquest heard yesterday.
He had earlier been at the funeral of St Annes postman John Chandler, where most of the mourners, including Mr Kirkham, were wearing Blackpool FC shirts.
Witness statements from a group of 15-year-olds, who cannot be named, say Mr Kirkham, of Walter Avenue, St Annes, and some of his friends had been walking along Park Road, on the opposite side of the road to the takeaway, at around 11pm.
One of the youths shouted from inside Zeko’s a Preston North End chant.
Blackpool and Fylde coroner Alan Wilson heard around six of the Blackpool fans crossed the road and surrounded Sean Beaumont, 32, who had been waiting for his takeaway outside, believing he was the one who had shouted.
One of the men, David Chandler, grabbed Mr Beaumont by the throat or chest area, knocking him off balance.
The inquest heard Mr Kirkham then headbutted Mr Beaumont, who responded by punching out in his direction.
The blow knocked supermarket worker Mr Kirkham to the ground and Mr Beaumont was able to get away.
A post mortem revealed Mr Kirkham was two and a half times the drink drive limit at the time of the incident.
It found Mr Kirkham had died of inhalation or aspiration of his stomach contents due to blunt force trauma to the head and alcohol intoxication.
When Mr Beaumont returned to his home on Heaton Road, St Annes, a friend called police to report he had been assaulted.
When police arrived officers told him Mr Kirkham had died, despite friends, paramedics and police trying to resuscitate him.
During police interviews Mr Beaumont said he had punched out to get away, afraid he was going to get his head “stoved in”.
Reading a transcript of his interview to police, coroner’s officer PC Ken Lord said: “He wanted to get away, he could see them getting more and more agitated.”
Recording a verdict of lawful killing because Mr Beaumont acted in self defence, Mr Wilson said: “This has been a very, very tragic case.”
‘There are no winners in this case’, says coroner
Blackpool and Fylde Coroner Alan Wilson, said: “I do not think the main issue in this case was that it was a football-related incident, but more a drink-related incident.
“There are no winners in this case.”
The verdict of lawful killing meant there was no criminal responsibility in the death of Mr Kirkham.
The Crown Prosecuting Service said it will not be re-opening the case.