The second wave flung Roberto Vasquez’s 21-foot vessel upside down into the Fire Island Inlet, turning an after-work fishing trip Tuesday into a fight for survival for three men on a boat.

“When I saw the big wave come, I said ‘Oh my God, we’re done,’ ” Erik Flores, 30, of Amityville, one of two men rescued off Cedar Beach, said Thursday night. “When I got up out of the water . . . we called his [Vasquez’s] name. We were crazy looking around the boat and a lot of waves were coming on top of me and the other guy. We tried to get Roberto. We don’t see him anymore. We don’t hear him anymore.”

Suffolk police and the Coast Guard have curtailed searches for the missing boater from West Babylon after efforts that started Tuesday as a massive rescue mission by air and water, with help from NYPD divers and local fire department boats. By Wednesday night, as chances dwindled for Vasquez’s survival, authorities called it a recovery mission for his body, after 388 square nautical miles had been systematically searched.

On Thursday, the search will be “part of the routine patrol,” a Suffolk police spokesman said.

Vasquez, 50, grew a Wyandanch construction business from one truck years ago to several trucks now, primarily helping to build the area’s roads, said Flores, a deli worker.

A father of three, Vasquez always seemed to be joking, never angry, a friendly guy who often urged his friends to go fishing with him, his rescued friend said.

advertisement | advertise on newsday

Vasquez, said his friend, was “crazy with the fish.”

“He got three boats, one in the [boat] yard and two at his house,” Flores said. “Every time, when he gets out of work, he’d say ‘Oh, we’ll go fishing now. Let’s go.’ ”

On Tuesday, Vasquez called on Flores and his employee Carlos Hernandez, 36, of Wyandanch, to dip their rods for striped sea bass in the inlet, a known spot for the fish.

They caught only one undersized bass and had to throw it back, Flores said.

Suffolk Marine Bureau and other officers investigate an overturned boat on Tuesday, Oct. 11, 2016, near Fire Island Inlet. Photo Credit: Stringer News Service / A.J. Ryan

They were just west of the Robert Moses Causeway when a commercial fishing vessel approached and Vasquez wanted to move his boat out of the way, Flores said.

After the first wave hit, Vasquez ran to the steering wheel, but his friends told him not to move the boat and just hang on, his friend said.

Then the bigger wave hit as the boater was under the awning over the wheel.

“I heard him down there trying to get out,” Flores said, “but when I tried to help him, another wave came up and put me out of the boat.”

The last they saw of Vasquez was his hand gripping the awning, Flores said.

After searching for his friend, Hernandez swam to the commercial fishing vessel, which plucked him out.

advertisement | advertise on newsday

Until the Coast Guard and police marine bureau came for him, about 15 minutes after the boat capsized, Flores clung to the hull of his friend’s capsized boat. The waves had taken the boat a half mile from where it had overturned, he said.

“I stayed on the top of the boat, thinking of Roberto.” the survivor said. “I didn’t want to leave him.”

With Joan Gralla