The brutal attack began as the victim, in her 20s, was walking along Westend Street in Oldham at about 4.40am.
She was approached by a slim white man in his early 20s who pulled her onto a nearby AstroTurf pitch where he assaulted and raped her.
Police were called after the victim went to a nearby house for help.
She was treated in hospital and is being supported by specially trained officers.
The area around the AstroTurf pitch has been cordoned off.
The perpetrator, who was wearing dark clothing with a hood pulled over his head, is said to have mousy brown hair and a Manchester accent.
“It’s very distressing that a young woman has been attacked and raped in such a brutal way,” said Detective Inspector Ian Harratt.
“We are doing everything we can to find the person responsible.
“Although we believe it is an isolated incident, you will see extra officers in the area, carrying out house-to-house inquiries and gathering information.
“If you have CCTV cameras, please review your footage and contact our local team if you have anything which could help our inquiries.”
Anyone with information should ring 0161 856 9080. Alternatively, they can call Crimestoppers, anonymously, on 0800 555 111.