The stroller, carrying 9-month-old Daniel Zamara, was set into motion by a sudden gust of wind Tuesday as the boy's mother tended to his three siblings at the Brooklyn station, the New York Post reported Wednesday.
When 30-year-old Delroy Simmonds saw the stroller and baby hit the tracks, he jumped down after the boy and lifted them both back up to the platform as an incoming train halted just short of where the incident occurred.
"The train was seconds away. The driver was honking the horn and then stopped seconds before it got to them," said witness Khalima Ansari.
"He's a hero, no doubt about it," she said. "Anybody could have thought, 'Well, I don't want to lose my life,' but he didn't care. He just jumped down and he got the baby just in time."
Simmonds, who was on his way to a job interview, said his involvement was "just a reaction to seeing the stroller on the tracks."
Daniel's father, whose name was not reported, told the Post the boy was treated at Brookdale Hospital for a head wound.