Workers fixing a manhole in Columbus Circle made a blood-curdling discovery Tuesday: the decomposed body of an apparent drunk who stumbled inside and went undiscovered for two weeks, sources said.

Surveillance video showed the man plunging into the open, unattended hole at about 2:30 a.m. on Sept. 30 — and never reemerging.

The man had barged through a series of safety barriers set up by Verizon utility employees who were working underground at West 58th Street and Eighth Avenue, but who had left the hole unattended at the time of the incident.

It was unclear why the workers weren’t watching — but they had no idea he was inside when they finally closed the hole up, sources said.

The crew didn’t return until Tuesday, when they popped up the manhole lid and found the unidentified man’s rotting corpse lying face up on top of some wiring.

Police sources said the man had been partially eaten by rats and was badly decomposed by the time he was discovered.

“The smell was just unbelievable,” one worker at the scene said.

“Doing that kind of job you’d expect to find some strange things in manholes or in sewers, but this is a first,” the worker added. “I was shocked.”

EMS pronounced the man dead at the scene.

It is not known if the man died from the initial fall or if he survived and then died later.

The city Medical Examiner is due to conduct an autopsy and will make that determination when it rules on the cause of death.

Police said the man may have been homeless and described him as likely being between the ages of 30 and 40.

He was wearing a T-shirt and shorts when he fell into the hole.

The body was pulled up by rescue workers using a tripod shortly after 8 a.m.

Stunned passersby and rescue workers could be seen holding their hands to their faces to stave off the stench.

“How could someone even get down there without anyone noticing?” one woman asked as she walked past the disturbing scene.

Other New Yorkers have stumbled into uncovered Big Apple manholes in the past, but not with such dire and grisly results.

In March, a Staten Island teen received minor injuries when she walked into an open manhole while she was texting.

Alexa Longueira, 15, was walking with a friend when she plunged into the hole, suffering minor scrapes and cuts, according to a report in the Staten Island Advance.

In 2016, a 6-year-old girl fell about 8 feet into an open manhole outside Saint Mary’s Park Houses in The Bronx. The girl was plucked from the sewer by passersby, escaping the ordeal frightened but uninjured.

In upstate Buffalo, a 9-year-old girl broke both her ankles when she fell 12 feet into an open manhole in 2017 and was trapped inside.

Fox News reported at the time that the girl was in three feet of water for hours, and was only rescued after a passerby heard her screams.