A robber pulled a coat and bag over his victim’s head after targeting him in a play park.
He had asked to use his mobile phone and for money, but was refused.
As the 32-year-old victim turned to walk away, the robber followed. He grabbed him on the wrists before a struggle ensued between the pair.
It happened on Saturday at around 10.55pm in Peartree park.
During the attack the victim was punched in the head and face. The attacker then let go, but asked again for money.
The victim handed over an amount of cash, but ran away when the offender asked him for more money.
He sustained minor scratches, but did not require hospital treatment.
Det Con Wendy Cissell said: “This was a robbery in which a man was repeatedly harassed and then attacked.
“We are hoping that anyone who may have seen this robbery to come forward.
“We are looking for a white man, around 5ft 8ins to 5ft 10ins tall, of slim build. He has very short cropped hair, with a thin face, wearing a dark Parka-style jacket, with a large hood with fur round it. He was also wearing knee length shorts.
“I would encourage anyone with any information about the incident to please call the 24-hour Thames Valley Police enquiry centre on 101.”