Lamar Odom -- Flying to New York For Basketball Meetings

11:20 PM PT -- Lamar bailed on the flight to NYC. We're told he became uneasy about making the trip after we posted this story about his plans -- and he has not rescheduled.

Lamar Odom is flying to New York later today ... to meet with honchos from several basketball teams, and he's carrying what he claims is proof that he's clean and sober ... sources connected with Lamar tell TMZ.

Our sources say on Tuesday ... Lamar underwent blood and urine tests for drugs, and he tested NEGATIVE for drugs.

This is consistent with what other sources have told us about his time with the Kardashians on Tuesday. We're told he was lucid and showed no signs of being under the influence of drugs.

We're told Lamar has had private conversations with execs from several teams who have expressed interest in him, provided he could show he was clean ... and the purpose of the trip is to meet with them and possibly strike a deal.

Our sources also say Lamar wanted to go to New York to visit his family, and get away from "the negative energy."

And finally, our sources tell us Lamar says he's had his fun with drugs and is ready to re-start his basketball career. Fact is ... he's done that before.