Paul Lawrence, 51, was named as the victim of an incident in Gladonian Road, around 6am, on Sunday, January 28.
Heartfelt family tributes were paid last week to a ‘gentle soul’ who was ‘full of happiness and loved by all’.
The plumber and gas engineer lived in Cheal Way, half a mile from where he died.
An inquest – which was was opened in Chichester on Tuesday morning (February 6) – heard that the police received a call from ambulance crews ‘in relation to a suspicious cardiac arrest’ in a public place.
However, the victim's ‘head injury’ was ‘consistent with him falling and hitting his head’, a record of inquest stated.
The report added: "He is believed to have been punched by another male causing him to fall into the road.
"A Home Office Post Mortem was unable to confirm a cause of death and so further investigations are ongoing.”
The inquest was suspended whilst criminal proceedings are ongoing.
A 16-year-old boy was taken into custody after the fatal incident.
A spokesperson for Sussex Police said: "Having carefully considered the circumstances, he has since been released on bail with strict conditions, including a curfew, until March 14 as enquiries continue.”
Paul’s work colleagues and friends have organised a sponsored walk from Brighton Pier to Littlehampton on Saturday (February 10). If you would like to take part or make a donation, visit https://justgiving.com/crowdfunding/Paul-Lawrence1.