Jagdip Randhawa, 19, from Hounslow in London, was punched by professional fighter Clifton Ty Mitchell during a night out in Leeds in October 2011.
He hit his head on a concrete path after the assault.
At Wakefield Coroner's Court, a jury concluded failings at Leeds General Infirmary contributed to his death.
On Thursday, the jury foreman said punches to the head and the treatment in hospital had caused the Leeds university student's death.
He said the hospital "fell significantly below the standards expected and required, which exacerbated the injuries to the head".
"We believe that serious mistakes and serious errors in judgment were made by a doctor involved in treating Mr Randhawa in Leeds General Infirmary on October 12, 2011," he said.
The jury concluded the hospital treatment "did significantly contribute to the death", but the failings were not "gross" and did not amount to unlawful killing in this respect.
"On the balance of probability, we are satisfied that but for the neglect identified, Mr Randhawa would have survived or would not have died when he did," the foreman added.
Mitchell, from Derby, was convicted of manslaughter and jailed for seven years in 2012 after the attack.
A student died after he was placed on a faulty ventilator and starved of oxygen at a Leeds hospital following an attack by a boxer, an inquest has heard.