Police have reopened a decade-old attack investigation following the death of the victim - and are treating it as murder.
Ashley McGurk, known locally as Ashley Thomas, died in a care home in Rochdale in January 2021, having spent nearly ten years of his life needing specialist support.
The 32-year-old, from Harpurhey, suffered severe brain damage after he was seriously assaulted whilst walking home from a party near Harpurhey shopping precinct on Christmas Eve 2011.
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The unprovoked attack left Ashley in a coma for several months, and meant he had to spend the rest of his life in care.
Now, an extensive pathologist's report has confirmed that the assault 10 years ago ultimately caused Ashley's death, prompting police to reopen their investigation as a murder probe.
Three arrests were made after the attack and two males were released with no further action taken.
One male was charged but the case was dismissed by the court.
Paying tribute to Ashley after his death, his mother said: "Visiting my own son every day in his care facilities was absolutely heartbreaking to see and cope with for 10 long years and to know we still don't have justice so many years on is so devastating.
"Both Ashley and his family deserve justice which is why I would ask anyone to come forward with information. We want this nightmare to end once and for all."
Detective Sergeant Paddy Connell, from the City of Manchester Division CID, said: "This was a devastating incident for Ashley's family and we believe there will be people in the local area with information about the reported assault at the time that may be able to help Ashley's family get the justice they deserve.
"Ashley suffered such horrific injuries that he spent the last 10 years of his life in care facilities and was regularly visited by his mother who has suffered unimaginable emotional pain since the assault and has visited him every day over the last 10 years.
"Anyone with any information - no matter how small it may seem - is asked to contact us on 0161 856 4409 quoting crime reference number CRI/06A1/0001614/21.
"Someone out there will know something and I would urge them to get in touch - even if it's anonymously through Crimestoppers on 0800 555 111."
