Mobley announced his decision at a press conference at the Knicks' training center, where he confirmed he has hypertrophic cardiomyopathy. The condition causes the heart muscle to thicken, making it harder to pump blood, and the 33-year-old Mobley said he had no choice but to end his career.

"The specialists I've seen made it clear that my heart condition has gotten worse and I couldn't continue to play professional basketball without putting my health and life in serious danger," Mobley said. "As much as I want to keep playing in the NBA, I have no choice but to follow the advice of my doctors and step away from the league."

Hypertrophic cardiomyopathy was the leading cause of sudden cardiac death in people under 30 years old and was linked to the death of former Boston Celtics forward Reggie Lewis.

The Knicks acquired 33-year-old Mobley last month from the Los Angeles Clippers - a trade that may ultimately have saved his life. An EKG during his physical showed an irregularity with the heart, which Mobley already knew existed. The Knicks decided to perform a MRI exam, which revealed the more serious condition that previously had gone undetected.

Mobley then saw four specialists around the U.S., who performed additional tests and provided him literature about the disease that convinced him to stop playing.

"The doctors said to not chance it and I feel as though they're right, having an 8-year old son, having a long life ahead of me, it's the smart thing," Mobley said. "It's a tough thing to swallow, but things in life happen, but you have to keep going."

Mobley averaged 16.0 points in 11 seasons with Houston, Orlando, Sacramento and the Clippers. He was expected to become the Knicks' starting shooting guard after the Nov. 21 trade.