One of three men who bashed a 36-year-old to death in Adelaide's north earlier this year had a plaster cast on his right arm, police have revealed.
Mark Boyce was repeatedly punched, kicked and stomped on by his attackers in January in what police called a brutal and cowardly bashing.
Detective Inspector Greg Hutchins says detailed analysis of CCTV footage has determined that one of the men involved had a plaster cast on his arm.
"Obviously it is only a tiny piece of information, but potentially a very important breakthrough," Det Insp Hutchins said.
"We are hopeful that this can lead to the further unravelling of this case, and ultimately provide us with the evidence we need to lay charges.
"I'm asking people who may be connected with this case, this community or these people, to think back to January this year and consider who they are aware of who had their arm in plaster."
Police are also carrying out DNA elimination testing obtained from clothing Mr Boyce was wearing, Det Insp Hutchins said.
The victim was chased through a street at Elizabeth South in January and held down by the man with the cast until the other two men arrived, before the trio then bashed him.
Mr Boyce died in hospital a week later.
Last week his father Malcolm urged anyone with information to contact police.
"It is important to me that Mark is remembered as a young man who was taken too early by people who had no right to do that," Mr Boyce said.