Police have arrested the suspect they believe stabbed a young man to death during a clandestine late-night meeting in Adelaide's west.
William Holdback was found with critical injuries on Barrpowell St in Welland after a group of nearby musicians heard shouting about 1.30am on Wednesday.
Despite the musicians' best attempts to revive him, Mr Holdback died at the scene.
CCTV footage of the incident showed the 21-year-old arriving at the quiet cul-de-sac alone before meeting with two men in a dark BMW.
Given the hour and the location in an industrial area, it had "all the appearance of a clandestine meeting", Detective Superintendent Des Bray said on Wednesday.
"That, together with some other information we've obtained, makes us believe that it was to do with either a drug deal or the recovery of money."
Det Supt Bray said the footage showed that the conversation became heated, leading Mr Holdback to flee the two men, one of whom ran him down and stabbed him to death.
South Australian Police on Sunday said detectives arrested a 27-year-old man at his northern suburbs home and charged him with murder.
He was refused bail and will appear in the Adelaide Magistrates Court on Monday.
The BMW seen driving from the scene after Mr Holdback's death was also seized from the home.
Police interviewed the car's owner, who they believe is also responsible for the crime.
Detectives continue to compile evidence about that man's involvement in the alleged murder.
Police are appealing for anyone with dash-cam footage of the car to come forward.