The 28-year-old male victim was found collapsed in the street on Burgh Street, N1 at 11.50pm on Saturday, 11 July. His wallet and his Rolex watch were taken.
The London Ambulance Service took the injured man to a central London hospital where he was found to have suffered a bleed on the brain and a broken jaw.
Police enquiries recovered footage from a nearby camera which showed the suspects chase the victim, lean over him, and then flee the scene.
While the quality of the footage is not of sufficient clarity to identify the suspects, police are keen to speak with the driver of a dark coloured vehicle, possibly a Toyota Prius that stopped next to the scene while the suspects were still present, before driving away.
In addition, officers are keen to hear from anyone who has been offered a Rolex watch for sale. The stolen watch was a model 11621 Rolex, serial number 21MN2300.
Detective Constable Alejandra Gomez, who is investigating, said: “I am very keen to speak to anyone who can provide information concerning the identity of the suspects in this case.
“Similarly, I ask the driver of the Toyota Prius that slowed to a stop next to the scene to get in touch and tell us what you saw.”
Anyone with information should call police on 101, email, or Tweet @MetCC quoting reference Cad 798/12Jul.