NEW YORK -- Jeffrey Vanchiro, a popular Brooklyn Nets fan, died Sunday night from injuries he sustained when he jumped out of a second-story window at his father's house in Flushing, Queens, on Saturday night.

Jeffrey Gamblero, a popular Nets fan, died Sunday night due to injuries he sustained when he jumped out of a second-story window at his father's house in Queens. Laura Cavanaugh/Getty Images

Vanchiro, commonly known as Jeffrey Gamblero, was 38.

The Nets offered their condolences in a statement.

"On behalf of ownership and the entire organization, I am terribly saddened to learn about Jeffrey's death," Nets CEO Brett Yormark said. "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 will do a special pregame video tribute for Vanchiro at Tuesday night's game against the Miami Heat at the Barclays Center. In addition, Vanchiro's family is encouraging everyone to wear neon to the game. Vanchiro became known to Nets fans for wearing neon T-shirts under a personalized white No. 44 home jersey and having his dance moves displayed on the Barclays Center video screens.

Vanchiro, who was recently in the news after security removed him from Madison Square Garden without his prosthetic leg, sustained severe brain damage and a fractured spinal cord as a result of the fall, according to his fiancée, Kristi Evans.

Vanchiro had been in the intensive care unit Sunday on a ventilator at New York Hospital Queens.

Evans, in an interview earlier Sunday at the hospital, said she believed the Dec. 2 incident during a Nets-Knicks game at MSG changed Vanchiro for the worse.

"After that, he was a completely different person," an emotional Evans said. "He was paranoid. He was erratic. He was frightened. He was horrified. He was a bit delusional. And he was having a lot of trouble sleeping. He couldn't sleep at all. When he would sleep or try to sleep, it would only take about 10 to 15 minutes before he would wake up screaming, covered in sweat."

Evans took to Twitter to express her sadness over his death.

We lost a brilliant, unique, incredible man today. Please tell me your stories about Jeffrey Gamblero so I can share them with the world. — Kristi Evans (@TwittsMcGee) December 15, 2014

Said Madison Square Garden in a statement: "Our thoughts and prayers are with his family."

Three days after the incident at MSG, Vanchiro remained distraught and said he wasn't feeling like himself. He thought he'd need until the All-Star break to return to normal.

But Friday night in Brooklyn, Vanchiro was shown on the arena video boards dancing and enjoying himself. He later went to his fiancée's nightclub, but something wasn't right, Evans said. Still, Vanchiro danced a lot, and Evans figured it would relieve a lot of his stress.

"If you try to stay the same after a life-changing event, then you're lying to yourself because when your life has changed you are now a different person," Vanchiro said Friday in an interview with OurBKSocial.com that was published to YouTube. "I mean, I even got alter-egos going and stuff, but I'm not going to get into detail because the world's not ready for that."

"I had the worst week of my life," he continued. "You guys don't understand, but I'm putting myself through the same training that I did when I lost my leg. When my leg got chopped off, I was [feeling] horror and trauma, and I had to focus on getting back to what I had to do."

The next day, Vanchiro went to a friend's house, then told Evans he was going to stay with his father, Sylvester, that night. Evans told him she thought it would be a good idea, so Vanchiro could get some peace of mind. But an hour and a half after Vanchiro arrived, Evans got a call from Sylvester saying Vanchiro had jumped out of a window.

"He's never, ever exhibited any suicidal tendencies," Evans said. "He jumped out of the bed, ran down the hallway ... and then threw himself out of a window headfirst and landed on his head."

Vanchiro underwent brain surgery at the hospital and was breathing on his own initially, but his condition worsened significantly Sunday morning, and his brain stopped functioning, Evans said.

Several family members were at the hospital with Vanchiro, and Evans estimated 50 people came to visit him. At one point, security was limiting his visitors to two at a time because so many people were there.

Vanchiro grew up in Queens and Brooklyn. A fan of both the Knicks and the Nets, he idolized Nets point guard Kenny Anderson growing up. He wanted to be a professional basketball player but had to settle for being a superfan instead. Despite losing a leg in an accident, he loved playing sports.

Evans described in detail the events that unfolded at MSG, video of which quickly went viral. Vanchiro was asked by security to quiet down, but Evans said he wasn't cursing or offending anyone. Vanchiro politely refused, and security told him he had to leave, so Vanchiro took off his prosthetic leg as a form of peaceful protest.

Evans said Vanchiro also refused security's request to leave and told them that he had paid a lot of money for the tickets, he was a fan and he didn't deserve to be kicked out.

Security then picked up Vanchiro and removed him from the arena. Video shows him being dropped, which, according to Evans, caused his back to twist and his head to bump against the stairs several times. Vanchiro was then taken into the back of MSG, where he "was so traumatized and bawling hysterically," according to Evans.

After the incident, Madison Square Garden released a statement through a Knicks spokesperson: "An unruly fan was ejected after MSG security received multiple complaints from fans sitting in that area. The fan was warned multiple times before being removed. He will not be permitted back into Madison Square Garden."

Vanchiro found success playing professional poker and creating graffiti art in the city.

"He was a huge part of [the atmosphere at Barclays]. He definitely brought unique energy to the environment, and [his death] ... was tough for me to hear," Nets center Brook Lopez said at practice Monday. "He always brought positive energy. He always had our back. He was there for us. We were just proud to have him be a part of our organization and a part of our team."

ESPNNewYork.com's Ian Begley contributed to this report.