The judge at the manslaughter trial of the Hillsborough police match commander has directed a jury not to consider the accuracy of his claim that Liverpool supporters forced open a gate in the middle of the 1989 disaster.

David Duckenfield, the former South Yorkshire police chief superintendent in command of the FA Cup semi-final between Liverpool and Nottingham Forest, told Football Association officials that Liverpool supporters had forced a gate, rushed in and caused the casualties, the jury previously heard.

The judge, Sir Peter Openshaw, said it was “not in the least surprising” that, while the disaster was unfolding, Duckenfield said Liverpool supporters had forced the gate. He told the jury he was directing them “in clear terms” that Duckenfield’s explanation had “no significance in the case at all and you should put it out of your mind.”.

The jury had heard that at 2:52pm on 15 April 1989 Duckenfield gave the order for large exit gates to be opened, in response to an urgent request from a superintendent, Roger Marshall. This allowed a large number of people into the ground, alleviating dangerous overcrowding at the 23 Leppings Lane turnstiles, which were allocated to all 24,000 Liverpool supporters with tickets.

About 2,500 people came through exit gate C, and many went down a tunnel directly opposite, which led to the central “pens” 3 and 4 of the Leppings Lane terraces. A lethal crush developed, killing 96 people.

Football Association officials went to talk to Duckenfield in the police control box shortly after the match was stopped at 3:06pm, seeking an explanation for the developing chaos, they said. Glen Kirton, the FA’s head of external affairs, gave evidence at the trial that Duckenfield told the FA secretary, Graham Kelly, that Liverpool supporters had forced a gate open, rushed into the ground, and that had caused the casualties.

Openshaw pointed out to the jury that the prosecution’s lead barrister, Richard Matthews QC, did not refer in his closing speech to that explanation given by Duckenfield.

The judge referred the jury to the accounts of two people who believed gates had been forced at Hillsborough at 3pm. One was Ch Insp Malcolm Edmundson, who was on duty at South Yorkshire police’s Snig Hill headquarters listening to radio traffic. He relayed a message that Liverpool supporters had forced gates open and that Marshall was requesting the “inner gates” to be opened.

The other officer was Ch Insp Robert McRobbie, in the police control box at Hillsborough, who saw a previous short opening of gate C by the police at 2:48pm, and believed the gate had been forced. It was closed quickly, and Duckenfield ordered the gate to be opened four minutes later.

Referring to the evidence at the trial relating to those two officers, Openshaw told the jury that Duckenfield “had the impression” that gates had been forced.

“Since the impression that Chief Inspector Edmundson had, and indeed that [another officer,] Sergeant Goddard had, from listening to those [radio] messages, was that supporters forced their way in through the gates at Leppings Lane, and since Chief Inspector McRobbie came to precisely the same impression, it isn’t therefore in the least surprising Mr Duckenfield had that impression, and passed it on to Mr Kirton from the FA,” the judge said.

“Mr Matthews did not mention this fragment of evidence in his closing address to you, and therefore I direct you in clear terms, that as the evidence has turned out in this trial, what Mr Duckenfield said to Mr Kirton after the match has no significance in the case at all and you should put it out of your mind.”

Duckenfield denies the charge of gross negligence manslaughter relating to 95 of the 96 people killed. His barrister, Benjamin Myers QC, has argued that Duckenfield was inexperienced, not trained as a match commander or given a proper handover, that there were “a lot” of Liverpool supporters without tickets.

Myers argued the dangers of a crush in the pens was not foreseeable, even by more experienced Hillsborough officers.

Referring to evidence Duckenfield gave at the 2014-16 inquests, Openshaw said the prosecution had argued it was an admission of failure which meant “in effect, he was admitting the charges now made against him“. Myers, Openshaw said, had argued that that reading of the evidence did not take account of admissions having been made in hindsight, Duckenfield’s problems remembering the events, or the “provisos, qualifications and caveats” he had made.

The defence said that “when put in context,” Duckenfield’s evidence at the inquests “robustly set out his defence,” Openshaw said.

The jury is expected to be sent out on Monday to consider their verdicts on Duckenfield and on Graham Mackrell, the former Sheffield Wednesday secretary, who is charged with breaching his safety duty at work. Both men have pleaded not guilty.