Houston rejoined his former team late last week, two years after he was forced to retire because of chronic knee pain. However, the Knicks already had the maximum 15 players under contract, and Thomas said he only gave the 36-year-old guard an invite to camp because of his history in New York.

Houston's chances were even slimmer because he didn't join the team until 10 days after practices began. He cited the timing issue in his decision to walk away again.

"While my body and my knees, in particular, feel fine, I know what is required for me to be truly effective in the NBA again, and it involves a timing and progression that would not be fair to Isiah and the Knicks right now," Houston said in a statement released by the Knicks. "With the season opening less than two weeks away, I think it is best for the team to move on without me. I appreciate the opportunity that Isiah and the Knicks have given me, and I wish the team nothing but success."

Houston played only six minutes in his lone preseason appearance Wednesday at Boston, then sat out a game at New Jersey the next night.