A fight over a pair of sneakers turned deadly when a man pulled out a knife and stabbed his girlfriend’s son inside their Bronx home Tuesday night, police sources said.

Malcolm Jacob, 20, was visiting his mom’s Merriam Avenue apartment when he accused her beau of stealing a pair of shoes he had recently purchased before a fist fight broke out.

The confrontation eventually escalated, causing the killer to pull out the blade and drive it into the young man’s chest as his mom looked on in horror, cops said.

The woman’s boyfriend then fled the apartment and is still on the loose.

Jacob was rushed to Lincoln Hospital where he was pronounced dead.

Neighbors said the couple fought viciously on a regular basis in the apartment and in the hallway, and that cops have been called to the apartment many time before.

“I’m really sad for the young guy,” said Awilda Cruz. “He was too young to die.”

Cruz said the woman recently begged her to call the police as she and her boyfriend went at, saying that she feared for her 7-year-old daughter’s safety.

The lady in the boyfriend were having a fight, and the little girl was between them, a 7-year-old,” she said. “She grabbed me and she told me, ‘Please call the cops for my daughter’s life.’”