NBA

THE CORE OF THIS BELOVED FRANCHISE ROTS EVEN MORE

THE cruelest part is how badly this city misses legitimate professional basketball, how much it craves a return to respectability, even the slightest hint of it. And how regularly the Knicks find a way to break everyone’s heart. You can set your watch by them.

A week ago this morning, for a few brief, shining hours, the Knicks were the talk of the town again. People were buzzing. They’d beaten the Nuggets the night before with a thrilling fourth quarter that temporarily seemed to awaken the echoes. They couldn’t guard anyone even in victory, but you could almost overlook that. For once, you could talk about the Knicks above a whisper. Or so it seemed .

Then Dwight Howard arrived Friday night and smacked everyone around, and then old friend Pat Riley followed him two nights later, and it was bad enough to realize what a mirage that Nuggets game had been; bad enough to ponder the black hole of a West Coast swing that awaited.

And now, there is This.

The Knicks got good and drubbed by the Suns in Phoenix last night, a 113-102 schooling that wasn’t anywhere near as close as it sounds. Their $20 million point guard, Stephon Marbury, was 2,000 miles away. Five hours before tip-off, Marbury’s plane touched down in New York City. For a time, it looked like he was actually AWOL. Then he text-messaged The Post’s Marc Berman.

And never have the wonders of modern technology more eloquently explained away the rotting core of a once-revered sports franchise.

“I have one thing to say, and that’s I got permission to leave,” Marbury stated. “I would never leave my team on my own. What I’m telling you is that I got permission to leave from Isiah [Thomas]. He said I could go home. God bless. Peace be with you.”

Ladies and gentlemen, your New York Knickerbockers.

Really, this is simply the inevitable, if circuitous, climax to what was destined to be a doomed marriage from the moment Isiah acquired Marbury from the Suns nearly four years ago. From the start, once you cut through the sentimental homecoming storyline, you could tell this was certain to end badly.

On the one side, you had a stubborn, ego-maniacal megalomaniac. And on the other side you had a stubborn, ego-maniacal megalomaniac. Thomas wanted to believe his credentials as one of the greatest point guards of all time would matter to Marbury. But anyone who’s paid attention to Marbury’s professional career – and since he made a 2 1/2-year pit stop in New Jersey, many of us already had – knew that was a pipe dream. This was Starbury. This was the guy who’d once stenciled “All” and “Alone” on his ankle tape.

Marbury clashed once with Larry Brown; Thomas sided with him then. He clashed with Thomas right around this time last year, but they managed to get beyond that, “kissed and made up” according to the coach, and Marbury actually played some of the best ball of his career afterward.

Now, there is This. There is Thomas deciding to reduce Marbury’s role, and Marbury responding by getting on an airplane headed east. Regardless of whether he got permission – and all Isiah would cop to, continually, was that it was “an in-house matter we are keeping in house” – regardless of whether Thomas rented him a limo to the Phoenix Sky Harbor Airport, there is no excuse for Marbury bailing on his team. None. A lapse of judgment and professionalism compounded when his replacement, Mardy Collins, sprained his ankle early last night.

It goes without saying that this should expedite the end of what will ultimately rival Brown’s as the one of the most ill-fated homecomings ever.

And good luck to whoever wants Marbury, who is to basketball teams what Ted McGinley has always been to television programs, a one-man jump-the-shark formula. And good luck to the Knicks, whose very essence was built with Marbury in mind, who are once again thrust into the throes of chaos, shattering the hearts of New York’s most loyal fans one more time. This time after only six games. Avoiding the Christmas rush.

“He is welcome back, and we want him as a member of this team,” is what Thomas said of Marbury, his exiled cornerstone. If he really means that, then he’s asking to lose the last thread of professional credibility he had left. If nothing else, Isiah had always left no doubt who was in charge of the basketball operation at the Garden, for better or worse. The inmates never did overrun the world’s most famous asylum.

Until now.

michael. vaccaro @nypost .com