The former New York Knicks star, 40, is undergoing dialysis and desperately hoping for a new kidney.

He was once a high-flying sixth man who played for the New York Knicks at Madison Square Garden for five seasons.

But Nate Robinson is fighting for his life now: The 11-year NBA veteran is just 40 years old and is undergoing dialysis as he battles kidney failure.

Robinson says he knows he will die if he doesn't receive a new organ soon, but he continues to fight hard.

“I've got to stay here. I want to be around for the next 40 years, to be a grandfather and see my kids and take them to the gym and tell them stories about my time in the NBA with Bron and Cobb and the guys,” he told Men's Health in an interview published Tuesday. “I've got to fight for it.”

“Kryptonate,” as he became known to Knicks fans, was first diagnosed with kidney disease 18 years ago, not long after being selected in the first round of the 2005 draft by New York.

According to Men's Health, his kidneys are functioning at less than 15 percent of their optimal capacity, and he told the magazine he's on a kidney transplant waiting list in Washington state and hopes to eventually get on a national list.

Nate Robb also played for the Nuggets, Thunder, Pelicans, Warriors, Celtics, Clippers and Bulls. Along the way, the 5'9″ dynamo became the only player in NBA history to win the Slam Dunk Contest three times.

He last played in the league in 2016. He averaged 11 points and three assists per game during his career, but was known as one of the best players off the bench in the NBA.

For now, Robinson is waiting: Fewer than 60% of American adults are registered organ donors, and of those, fewer than 1% are suitable for a transplant.

Currently, there are more than 100,000 people nationwide waiting for an organ transplant. Americans can register to become an organ donor or find out more information about organ donation. Click here.