EAST RUTHERFORD, N.J. -- New Jersey Nets center Alonzo Mourning is leaving basketball again because the kidney disease he's had for three years is worsening and he needs a transplant.
The announcement Monday came just a few months after Mourning, 33, signed a four-year contract with the Nets believed to be worth $22 million. The four-time All-Star sat out all of last season and large portions of two of the last three years because of the life-threatening kidney ailment, focal glomerulosclerosis.
The team said Mourning, who was in his 12th NBA season, needs a transplant "in the near future" and that a nationwide search is under way for a prospective donor.
"Alonzo is a true champion and a very courageous athlete who attempted to defy the odds with his comeback to the NBA," Nets president Rod Thorn said. "Unfortunately, his medical condition will not allow him to continue his basketball career."
Dr. Gerald Appel of Columbia University Medical Center said Mourning's kidney function has deteriorated rapidly in recent weeks.
"It is no longer medically safe for him to play basketball," Appel said. "Although he still feels well, the chemical imbalances in his blood make it dangerous for him to play."
Mourning played in 12 games for the Nets this season, averaging a disappointing 8 points and 2.3 rebounds in 17.9 minutes. His career averages were 20.3 points and 9.8 rebounds per game coming into this season.
On Saturday, Mourning had a season-high 15 points in the Nets' 81-80 loss to the Toronto Raptors. Two days earlier, he got into a heated exchange with teammate Kenyon Martin, who made light of Mourning's disease.
"I have overcome all I have overcome to come back and play this game for one reason, and that's to win," Mourning said afterward.
Mourning previously played for the Charlotte Hornets and Miami Heat.
The disease was detected in 2000, while Mourning was with the Heat. The diagnosis came shortly after the 6-foot-10 center helped the U.S. team win the gold medal at the Olympics.
The disease attacks the tiny filters in the kidney that remove waste from the blood. That makes the kidney spill protein from blood into the urine. The resulting kidney damage can lead to kidney failure, which requires dialysis or a transplant.
"It's a sad day in anyone's life when they can on longer do what they love, especially when they have no control over their situation," Heat president Pat Riley said in a statement. "Alonzo had been the cornerstone of the Heat organization for eight years and continues to be a role model in the Miami community."