Two of the three cyclists involved in the road rage attack on a car driver in Hove on Sunday have been interviewed by police.
Detectives have issued a fresh appeal for the third man – believed to be called Paul – to hand himself in.
The three cyclists are believed to be friends.
The third man is being sought after a 52-year-old car driver was punched and knocked out in Portland Road, Hove, just before noon on Sunday.
He was attacked after opening the door of his Jaguar car in the path of the cyclists.
He is in a specialist head injuries hospital where his condition is critical though stable.
Detective Inspector Lee Horner, who is heading the investigation, said: “Extensive inquiries have been made by a team of detectives working on this case and I am now keen to speak to a man called Paul, who may be able to significantly assist us with this investigation.
“He is believed to live in the Seven Dials area of Brighton, possibly near Brighton, Hove and Sussex VI Form College (BHASVIC), and is known to visit The Level and Brighton skate park regularly.
“I am appealing directly to Paul and to anyone who thinks they know him to come forward.”
The suspect was described by Sussex Police as a white man, in his late thirties, 6ft tall, with a distinctive Roman nose and dark brown greying hair in a curtain style.
He is known to be a retro bike enthusiast.
One of the cyclists was arrested yesterday after handing himself in to Brighton police station at about 4.45pm yesterday.
The 36-year-old man from Brighton had seen the media coverage of the incident.
He was interviewed then released with no further action being taken.
Another of the three cyclists has already been interviewed without being arrested.
Detectives have looked at CCTV camera footage and plotted the cyclists’ route eastbound along Old Shoreham Road, Portslade.
They were seen to turn right into Boundary Road before heading along Portland Road where the attack took place.
The 52-year-old victim from Hove was attacked after opening his car door, causing the cyclists to take avoiding action.
He suffered a serious head injury and was taken to the Royal Sussex County Hospital in Brighton.
He was later transferred to Hurstwood Park Neurosciences Centre in Haywards Heath where he is now being treated.
A fourth cyclist, not part of the group of three, stopped and gave first aid to the victim.
Detectives urged anyone with information to call them on 0845 6070999.