Tim Hardaway Jr. hit a fadeaway game-winning jumper with 8.2 seconds left as the Knicks who blew a 23-point fourth quarter lead defeated the rebuilding Celtics 103-102 in their preseason opener.

The first-round pick with his father seated just 10 feet from the court finished with 16 points off the bench and hit 6 of 10 shots. Hardaway Iman Shumpert and Metta World Peace combined for 47 points off the bench on 18-for-26 shooting. Shumpert was outstanding making all seven of his shots and scoring a game-high 18 points. When he came out late in the second half he turned to teammate Kenyon Martin “I’m pissed off early this year.”

“That’s just how I play” Shumpert said afterward. “I ain’t gonna be quiet about it anymore. I got a chip on my shoulder.”

The forward formerly known as Ron Artest played 22 minutes and scored 13 points mostly from outside. He wore his purple and gold Lakers sneakers for his Knick debut saying that his orange and blue sneakers hadn’t arrived yet.

Metta held court for several minutes after the game and delivered a few gems. He said his comments don’t mean anything until June and later added “honestly I forget stuff so fast. Like today I asked big fella ‘we go to Toronto (tomorrow) who do we play?’ ” Andrea Bargnani who returns to Toronto on Friday scored 12 points in his Knicks’ preseason debut but made just 3 of 8 shots. Carmelo Anthony scored seven on 3-for-9 shooting. Raymond Felton added 11 points while Tyson Chandler had eight. Kenyon Martin dressed but did not play. There is a chance he’ll sit out the next two preseason games.