Hillsborough match commander David Duckenfield is facing "bitterly unfair" blame for the disaster that left 96 football fans dead, his retrial has heard.

Bad planning, stadium design, crowd behaviour, police behaviour, individual mistakes and genuine human error all played a part in the tragedy, Benjamin Myers QC, defending 75-year-old Duckenfield, told the jury as he made an opening speech on behalf of the defence.

The defendant, a chief superintendent with South Yorkshire Police and the match commander with responsibility for policing the game, denies the manslaughter by gross negligence of 95 Liverpool supporters who died in the crush at the FA Cup semi-final match between Liverpool and Nottingham Forest at Sheffield Wednesday's ground on April 15 1989.

Around a dozen relatives of the victims of the disaster sat in the public gallery at Preston Crown Court watching proceedings.

Mr Myers said the fans who died are "at the heart" of the case.

He added: "The emotions stirred by this tragedy were powerful. How could they not be?

"In no way do we seek to insult Liverpool Football Club or its supporters or the city of Liverpool itself.

"Whilst heartfelt sympathy for those who suffered is natural, it is human, it must never be a reason to convict someone for events beyond his control or responsibility.

"It is blatantly unfair to blame one person when so many other people and so many other factors contributed to this tragedy."

Mr Myers told the jury the prosecution were "confusing" the defendant's responsibility as the match commander and criminal responsibility for what went wrong.

He said Duckenfield was only made match commander 19 days before the game, after being appointed as chief superintendent for "F" Division of South Yorkshire Police where the stadium was situated.

But he had never been match commander at a football game before, let alone for a 50,000-capacity cup semi-final, and was "not the ideal man" for the job but "just got on with it", as that was how South Yorkshire Police operated, Mr Myers said.

Jurors have heard all of the 24,000 Liverpool fans were directed to the Leppings Lane end of the ground, where limited turnstiles served a bottleneck of a very large crowd, ahead of the 3pm kick-off.

The court has heard Duckenfield acceded to requests to open an exit gate to the stadium after crushing built up outside the turnstiles before the match.

Once through exit gate C, spectators saw a tunnel marked "standing" which led to the central pens on the terrace where the fatal crush happened.

Mr Myers showed the jury Hillsborough Stadium's safety certificate, which showed a 7,200 crowd capacity for the West Terrace, at the Leppings Lane end of the ground where fans were crushed to death.

He said the true safe capacity was 5,426 - around 1,800 or 25% overestimated - but nobody, including Mr Duckenfield, realised it at the time.

"If the central pens were already too full when David Duckenfield gave the order to open the gates, why did no-one else appreciate they were too full?" Mr Myers said.

"He's expected to see a problem nobody did."

Police manpower had also been cut by 15% from the semi-final at the same ground between the same two teams the year before, the court was told.

But again it was a decision taken in the planning for the match prior to the defendant's appointment as match commander and nothing to do with the defendant, Mr Myers said.

He said police radios on the day became "unworkable" as the disaster unfolded, which again cannot be blamed on Duckenfield.

Mr Myers also said the world of football was very different from today, with terraces, fences and sometimes "sudden outbreaks of mass disorder and even violence".

He added: "The tragedy was the consequence of many factors, look closely at Mr Duckenfield of course, we say bad planning, crowd behaviour, police behaviour, mistakes by individuals and genuine human error.

"This, or something like this, was going to happen sooner or later.

"He's being placed in a position of ultimate blame, not just his part but for the shortcomings and failures of others, factors beyond his control and even knowledge, and that is deeply and bitterly unfair."

The trial, which began last week, has heard it is the prosecution's case that Duckenfield's failures to discharge his responsibilities were "extraordinarily bad" and contributed substantially to the deaths of the fans.

The court was told a previous trial had taken place in January but the jury was unable to return any verdict and was discharged.

Ninety-four of the victims died on the day of the disaster, while Lee Nicol, aged 14, died two days later from his injuries.

Twelve of those who lost their lives were from Wirral and Ellesmere Port.

The court heard the 96th victim, Anthony Bland, suffered brain damage and remained in a permanent vegetative state until he died in March 1993, which meant his death was out of the time to be classed as resulting from manslaughter.

The trial continues.