The attack happened between 1.10am and 1.25am on Sunday 21 April 2013 when a man was paying for petrol at a filling station on Rowlandsway.
He was approached by two men. One of them screamed down his ear, the victim turned around to look at the offender who shouted racist comments at him.
The victim tried to ignore him, but he continued to shout racist obscenities and then punched him in the face.
When he tried to get away his assailant followed him and punched him again about five times in the face and ran off in the direction of Rowlandsway.
The offender is described as a white man in his 20s, of muscular build with brown cropped hair. He wore a blue shirt, light trousers and spoke with a local accent.
Police Constable Cheryl Williams from Wythenshawe police station, said: “This was a totally unprovoked attack on a man who was filling his car with petrol.
“The offender racially abused him, before subjecting him to a sustained attack which left him traumatised.
“If you recognise this man or were in or around the filling station in the early hours of that morning and witnessed the assault, please contact the police.
“Greater Manchester Police takes all reports of racial abuse, whether it be verbal or physical, extremely seriously. We are doing all we can to find the culprit so he can be brought to justice.”
Anyone with information should call on 101 or the independent charity Crimestoppers, anonymously, on 0800 555 111.