A stranger randomly slugged a 65-year-old Queens man — sending him headfirst into the ground in a brazen, broad-daylight attack, cops and the victim’s wife told The Post on Tuesday.

Nikolin Marashi had been working in the compactor room of a Flushing building when he stepped outside to take a tenant’s phone call at about 9:45 a.m. on Friday, according to Marashi’s wife, Rita.

He had gone outdoors because cellphone service in the compactor room was spotty, his wife told The Post on Tuesday.

That’s when a shades-wearing menace walked up to him on the corner of Franklin Avenue and Union Street and clocked him in the face, knocking him clean off his feet, cops said.

“He fell and hit his head on the asphalt,” Rita told The Post on Tuesday afternoon. “He was lucky to bang on the car first, and after he fell on the street. He has bruising, swelling, a big bump.”

Marashi’s minor injuries put him in New York- Presbyterian Queens Hospital, where he was listed in stable condition, his wife said.

By Tuesday, however, the blue-collar hero was already back at work.

“We have to work for a living, especially today when it’s snowing,” Rita, 62, said. “Nobody covered his job. I’m trying to help him. He’s so upset and I’m upset. I don’t know what to say.”

The suspect — who fled on foot — is described as a man with a medium complexion.

Besides the sunglasses, he was last seen wearing a black hat, an orange hooded sweatshirt, black pants, and white sneakers.

No arrests have been made, cops said.

Rita, who said both she and her husband are Albanian immigrants, hopes the cops catch up with the violent ruffian before he goes after someone else.

“Maybe tomorrow, maybe the next day he’s going to hit a woman, a kid, another man,” Rita said. “I cannot understand what’s going on.”