A 33-year-old man was running along Stanley Road in Handforth at 3pm on Sunday, 30th May, when he accidentally knocked the back of a black Mercedes that was parked on the curb.
The man carried on running along Manchester Road towards Wilmslow when the Mercedes pulled up alongside him.
A man got out of the car and assaulted the victim using a plate. The suspect then ran away from the scene in the direction of Handforth.
The man sustained facial injuries and was taken to Wythenshawe Hospital for treatment.
An investigation has been ongoing and officers have been following a number of lines of enquiry.
PC Hollie Geal, of Macclesfield Local Policing Unit, said: "Since the assault took place we have been conducting CCTV enquiries and attempting to speak to a number of witnesses who are believed to have seen the assault take place.
"As part of the investigation I am encouraging anyone with information to make contact with police or if you have dash cam or CCTV footage that hasn't been provided to us then please get in touch.
"If you think you may know the identity of the offender or were in the area at the time and not yet spoken to officers please come forward."
If you have information please contact Cheshire Constabulary on 101 quoting IML 1000649 or Crimestoppers anonymously on 0800 555 111.