NBA

MARCH BADNESS

These Garden fans deserve so much better.

Isiah Thomas was a Hall of Fame player with the Pistons. He’s now a Hall of Shame coach/president with the Knicks.

The mighty Pistons were in town last night as the Knicks lost again. But salute the sellout crowd at the Garden, up on its feet in the final 20 seconds, chanting “De-fense” playoff-loud, with the Knicks down two.

The chants didn’t help as Tayshaun Prince (28 points) hit a running lefty drive with 9.9 seconds left, clinching Detroit’s 101-97 victory before a crowd that had no business being this lively.

The Knicks are dead, and the one-year anniversary of Thomas’ ridiculous contract extension comes Tuesday. All around the city everyone wants Thomas to pack his bags next month, but, inexplicably, the fans are still showing up at the Garden, still cheering them despite the historic mass of losing. Must be Friday night Happy Hour.

Where’s the boycott? The fans don’t even chant “Fire Isiah” any longer, realizing it’s a moot point for now.

Despite their decent effort against a Pistons’ squad missing two starters, the Knicks (18-44) fell 26 games below .500 in a collapse stunning even by Knick standards. They are 0-3 on the homestand and could close it out 0-4 with a loss tonight against the Blazers.

“I think we’ve been consistently competitive for a while here,” Thomas said. “We haven’t been able to close out close games. Our fans have been great the whole season, showing up, supporting us. Tonight we have another sellout. I think people enjoy the basketball that’s being played.”

Or rather the standards have fallen deeply at The Mecca.

The Knicks hold the second-worst record in the East, fifth-worst in the league. Monday marks the anniversary of the game that changed the future of the franchise when Steve Francis beat the Wizards in Washington with a buzzer-beating 3-pointer. That elevated the Knicks into the eighth seed with a 29-34 record, and the next day owner James Dolan boldly bestowed Thomas with a contract extension.

Dolan hasn’t been heard from since. Neither have the Knicks. Their record since the extension is 22-59 (.272) after finishing up last season at 4-15.

The only thing left this season is lottery positioning and seeing if rookies Wilson Chandler, making his second start, and center Randolph Morris can play.

Chandler logged another 25 minutes but was ineffective (six points, 2-of-4) as Quentin Richardson received a DNP – the only Knick not to play.

Despite Eddy Curry’s powerful game (team-high 23 points), Thomas chose to let Morris run in the fourth quarter, though he didn’t score or take a shot.

“I’m trying to get them as many minutes as we possibly can,” Thomas said.

*

Stephon Marbury was on bench, perhaps scouting his next club. Detroit is a logical destination if he gets bought out because Marbury and coach Flip Saunders get along. Marbury and Saunders hung out for 10 minutes in the trainer’s room of the Detroit locker room after the game. …

Before the game in the hallway, Thomas and Marbury exchanged a hearty handshake. Interesting. …

Zach Randolph returned to his home state of Indiana yesterday to attend to another family member’s emergency. Randolph, whose grandmother died in November, causing him to miss part of November’s doomed West Coast trip, was to miss last night’s game vs. the Pistons with a sore foot even if he had stayed. But now he’ll miss his grudge match game tonight vs. the Blazers, who traded Randolph on draft night and went from awful to a winning team. …

Blazer F Channing Frye, their 2005 first-round pick, makes his Garden return. The Knicks could have had Andrew Bynum over Frye.

Pistons 101 Knicks 97

marc.berman@nypost.com