The victim told cops she was jogging on South Lake Drive inside the iconic greenspace around 5:15 a.m. Sept. 17 when the menace approached her, slugged her multiple times and plunged an unknown object into her back, the sources said.

The attacker, who was wearing a face mask, black hoodie and black pants, fled after the random ambush, according to the sources.

The woman went on her own to SUNY Downstate Medical Center, where she was treated for a puncture wound to her back, the sources said.

She walked into the NYPD’s 78th Precinct on Thursday to report the random assault — and when asked about the delay in reporting, she said she was waiting for hospital discharge papers, according to the sources.

No arrests had been made by Friday.