PC Liam Stewart, 33, from Hoyland, was charged with assault occasioning actual bodily harm (ABH) following the incident in Sheffield on August 8, 2017, in which 18-year-old Louis McAndrew suffered a broken nose after allegedly being held by the throat and hit by the officer.
Stewart - who can be identified as being from Hoyland after reporting restrictions were successfully challenged by the Chronicle at a hearing earlier this year - claims he was acting in self-defence.
CCTV footage of the incident from an optician shop across the street, and handheld footage captured by a police officer, were shown to Leeds Crown Court on Wednesday.
Prosecutor Ian Brook said: “What he did in delivering those three punches, in particular the last one, was quite unreasonable and totally disproportionate to any contact the complainant made to him or any future threat he may have perceived as imminent.
“Putting it colloquially, we see the defendant went over the top in his dealings with this youth.”
Chesterfield fan Mr McAndrew had travelled to see his side play Sheffield Wednesday at Hillsborough with a group of fans.
They had been to several pubs in the city centre before getting in taxis to the Hillsborough Tap.
Mr McAndrew, who was in the first taxi, was served in the pub before being asked to leave as he was an away fan.
He then went back into the pub to warn some friends who had arrived later - it was then that police were called and several officers arrived, serving the fans with section 35 orders that banned them from the match.
Mr Brook said Mr McAndrew was upset at this, after he had ‘taken half a day holiday from work, spent money on a ticket and the price of his train fare’ - but he complied with the officers and turned to walk back towards the city centre.
Two officers, one of which was Stewart, then chased after the teenager, according to the prosecution.
Mr Brook added: “It seemed to the complainant that these two officers were looking for some form of confrontation.”
He said Mr McAndrew will tell jurors that Stewart had held him by the throat against a shop’s shutters so that he couldn’t breathe.
As he tried to push the officer away, he raised his arms, and Mr Brook said the defendant had made statements that Mr McAndrew was swearing, spitting, flailing his arms and clenching his fists, which the complainant denies.
Mr McAndrew also denies the defendant’s claim that he was ‘heavily in drink’, saying he had four pints across the four-to-five hour period.
Stewart claims the teenager had taken his jacket off and dropped his shoulder as if to punch him, which Stewart believed was ‘the last straw’ that he should take defensive action.
He also denies grabbing Mr McAndrew by the throat, instead saying he held his t-shirt - which was allegedly ripped in the incident, with photos of this being supplied to jurors.
The CCTV footage shown in court was originally found by Mr McAndrew’s parents, who following the incident asked the shops in the area to find out more about what happened to their son that caused him to need several hospital appointments to treat his broken nose.
This footage was also passed onto the Independent Police Complaints Commission.
Mr Brook added that Stewart said he was ‘acting in self-defence, and that the force that he used was necessary, reasonable and proportionate’.
The prosecutor said the jury will hear that some of the group were associated with ‘football hooligans’ known as the Chesterfield Bastard Squad.
The prosecutor said the defence will tell the court the Mr McAndrew was attached to the group, which he will deny.
In the police-shot footage, Mr McAndrew can be heard saying ‘I’ve got a ticket, I’ve got a season ticket, I’m a true fan, I’ve done nothing wrong’ to the officers.
Stewart denies assault occasioning actual bodily harm.
The trial continues.