The 34-year-old was walking on Mill Lane towards St Vincent’s Road just before 10.30pm on Thursday when he was approached from behind and attacked.
His wallet was stolen, and he suffered cuts to his mouth and a minor injury to his knee.
Because the victim did not see his attacker, or attackers, police have not released a description but said the man thought they were male.
Police have asked anyone who saw the incident or was driving through and has dash cam footage to get in touch.
Call 101 and quote reference number 44190372567.
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