A 14-MONTH-OLD baby was hospitalized yesterday with minor injuries after she tumbled facedown in a stroller off a subway platform onto the tracks below.

At 12:46 p.m., the baby's mom, Teneka Greer, 28, of West Philadelphia, was standing on the platform of the Market-Frankford line at 56th Street about 5 feet from the tracks.

WATCH: Video of Greer saving her daughter.

Her daughter was seated in a jogging stroller. Greer became distracted and let go of the stroller, which was not in a locked position. What happened next was captured on video surveillance.

The stroller slowly rolled toward the eastbound track and toppled over onto the rail with the child inside.

Greer immediately jumped onto the tracks and pulled her baby out of the stroller. A man standing on the platform took the child from her.

Other passengers ran over to help and a woman hit the emergency call button, which alerted SEPTA police and dispatch.

Within 19 seconds of the baby falling on the tracks, SEPTA was able to stop an incoming train from 60th Street, said Scott Sauer, SEPTA's system safety director.

If that train had started to move, it could have arrived at 56th Street in less than a minute, Sauer said.

Paramedics arrived, and the baby was taken to Children's Hospital of Philadelphia to be treated for lacerations to the forehead. The baby is expected to fully recover.

Greer, who could not be reached for comment, will not face charges, because SEPTA police say the incident was an accident.

"It's a bad situation that could have potentially been tragic," Sauer said.

The fall serves as a reminder for customers to be alert while standing on the platform and to always lock the brakes on strollers while waiting for a train, SEPTA officials said.

SEPTA employees were shaken when they watched the video.

"It's heart-wrenching because the stroller moves at a slow rate of speed, and you want to tell someone to grab the stroller," Sauer said.