A teenager is in stable condition after he collapsed while playing in a high school basketball game.

John Maro, 15, was playing for Basking Ridge's St. James School. The game was held at Auten Road Intermediate School in Hillsborough Saturday evening.

Coach John Travers says the game had just started and Maro has already scored four points when he collapsed.

Maro’s father and other parents ran onto the court and started performing CPR. Coach Travers called 911. A defibrillator was used to shock Maro’s heart, and he was taken to Robert Wood Johnson University Hospital.

On Monday, the teen was reported to be doing well.

“Johnny was sitting up in the hospital bed. He was actually able to sit on the side of the bed this morning. And was talking with his parents,” Travers says. “It just put the biggest smile on my face. He’s a very good friend of my son. They play on two basketball teams.”

Family members tell News 12 that the eighth grader was born with pulmonary valve stenosis – which is a narrowing of a heart valve that can restrict blood flow.

Maro had a valve transplant two years ago and doctors cleared him to play basketball. Maro’s father says that this medical issue had nothing to do with his son’s collapse on the court. The parents say this is concerning because they now need to figure out what happened.

The doctors at the Children’s Hospital of Philadelphia, where he is being transported, will now try to determine why Maro collapsed.

Travers says that he is grateful for the Hillsborough Police Department, and he wants them to know how thankful he is that they were able to help save Maro’s life.