The assault happened after the attacker shouted something at the victim on the platform of the station.
The victim, a man in his 20s, removed his headphones and was then racially-abused and punched in the head by the man.
Today police released a CCTV image of man they are trying to trace in connection with the offence, which happened at around 10am on September 17.
A British Transport Police (BTP) spokesperson said: "The victim recalls seeing the same man previously at the station, he was staring at him and muttering under his breath. Thankfully the victim avoided any serious injury, however he received swelling to the side of his face.
"This random and unprovoked assault has left the victim feeling nervous when using the station as he is frightened of the man returning and assaulting him further."
Anyone with information can text BTP on 61016, or call 0800 40 50 40, quoting reference 340 of 17/09/2017.