Police have arrested the man who stabbed a teen during a fight on a subway train in Bushwick over the weekend, authorities said.

Alton Chesney, 46, was captured Tuesday and charged with knifing the 19-year-old man Saturday around 3 p.m.

The two got into an argument that eventually turned physical as they were riding a northbound J train near the Chauncey Street station, police said.

A video recorded by a fellow straphanger shows Chesney struggling with the victim before stabbing him with a sharp object in the lower abdomen, police said.

The injured man staggered off the train when it pulled into the station and found his way to Brookdale Hospital, where he was treated for non-life-threatening injuries, police said.

Chesney was charged with assault.