Thirty-eight-year old Jeffrey Gamblero, whose real name is Jeffrey Vanchiro, apparently jumped out of a second-story window of his father's home in Flushing.
Gamblero made news recently when he was ejected from Madison Square Garden without his prosthetic leg.
His fiance, Kristi Evans, tweeted Sunday night that he died at the hospital. And the Nets issued a statement mourning his death.
However, his sister, Audrey Livingston said Monday morning that he is still alive, but in grave condition.
Vanchiro was sleeping at his father's home Saturday night when he suddenly awoke, and in a disoriented state, ran down the hallway and towards the window and went out it head first, falling one story to the ground.
The sister said she does not consider it a suicide but cannot explain his actions, other than he was disoriented.
Family members seem to agree Vanchiro was not the same after the Dec. 2 incident, when MSG security ejected him from a Nets-Knicks game.
Here is the text of the statement from the Brooklyn Nets and Barclays Center CEO Brett Yormark:
"On behalf of ownership and the entire organization, I am terribly saddened to learn about Jeffrey's death. A proud Brooklynite, Jeffrey was a passionate Nets fan and one of our most visible and loyal supporters. I was delighted that he joined the team on our trip to London last season and I always enjoyed his enthusiasm while dancing and cheering during Nets games at Barclays Center. The entire organization expresses our deepest condolences to his family and friends. He will be missed.
The Nets plan to honor Gamblero during Tuesday night's game against the Heat at Barclays Center.
Still, hospital officials confirm that Gamblero remains in critical condition at New York Hospital Queens.