An 18-year-old man was fatally stabbed onboard a “D” subway train near Barclays Center in downtown Brooklyn after getting into a fight with another rider Thursday night, police said.

The NYPD received a 911 call just before 11:30 p.m. about a man who had been stabbed on a northbound “D” train as it entered the Atlantic Avenue-Barclays Center station.

Officers who responded to the scene found the 18-year-old victim suffering from a stab wound to the abdomen.

EMS rushed the teen to New York-Presbyterian Brooklyn Methodist Hospital, where he was pronounced dead.

He has yet to be publicly identified pending the notification of his family.  

According to the police, a preliminary investigation has uncovered that the stabbing victim had gotten into a verbal dispute with another man, which escalated to violence when the attacker stabbed the teen with an unknown object.

The suspect then got off the train, exited the station, and fled in an unknown direction.

Cops said no weapon was recovered from the scene, and no arrests have been made as of Friday morning.

Police told The Post it is not known what the two men were arguing about before their dispute took a deadly turn.

There was no description of the suspect immediately available, and no surveillance footage has been released.