The 19-year-old female victim, from Rotherham, was attacked at the top of the stairs onto the station’s overbridge, where there had been some “slight accidental nudging”.
Police say that as a result of the attack she suffers from panic attacks and is now too scared to enter the station or catch a train.
According to British Transport Police, who are appealing for witnesses to the assault, it took place on the West End overbridge at 8.30am on March 3.
The force said in a statement: “The victim, from Rotherham, had left her train and was walking up the stairs onto the station overbridge.
“Due to the large volume and flow of people, some slight accidental nudging was taking place between the crowds. Once at the top of the stairs a woman approached the victim and punched her in the face.”
Pc Dan Worthington said: “The victim was left with cuts and bleeding to her face. She has also been left extremely shaken by the incident.
“She suffers from panic attacks and this experience has affected her so much she is now unable to enter the station or catch a train.
“No –one should have to be subjected to this level of unprovoked and violent behaviour. It is vital that we trace the person responsible and bring them to justice.
“We believe the women pictured may be able to help with our enquiries. Who is she? If you recognise her please contact us”
Anyone with information is asked to contact British Transport Police on 0800 40 50 40, or text 61016, quoting reference 365 of 4/3. Information can also be passed anonymously to the independent charity Crimestoppers on 0800 555 111.