NBA

Be grateful for this Knicks’ season, but next one must be great

The last gasp was snuffed by a whistle. The Knicks had done everything imaginable to whittle a 23-point lead to four, and now the cushion was six, the ball was in Shawne Williams’ hands, he was driving to the basket, and 19,763 people were ready to lift the old building into orbit.

Paul Pierce was back. He slid over to impede Williams. There was contact, and Derrick Collins blew his whistle. The ball kissed off the backboard, splashed through the net, and Madison Square Garden was apoplectic. They hadn’t come to this Easter Sunday matinee seeking a miracle, just a sign that the Knicks were as eager as they were to keep the season breathing a few more days.

Now they had this.

Only, they didn’t even have this. Collins pointed the other way, waved off the basket, called Williams for a charge rather than Pierce for a block. And that is where the season would die. There were still five minutes and seven seconds left in the game. The spread was still only six. But sometimes, you know. No need for a coroner. Game over. Series over. Season over.

“I liked the heart,” Knicks coach Mike D’Antoni said when the 101-89 Celtics win was over, when the sweep was complete, when summer arrived two months early. “But Boston today is a better team than we are in every sense of the word. They’re a better team. We have to get up to that level.”

So this was more than the end of a basketball season, in truth; it was also the last time the Knicks will be graded on a curve, judged against the decade of nonsense that preceded this season.

That goes for everyone, from Donnie Walsh (if he stays) to Mike D’Antoni (who will — and should — get next year’s likely mini-season to prove he has the goods to belong here) through whichever players return and the others still to be acquired.

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The Knicks were a fine story this year, a fun story, because New York has been so starved for basketball relevance that its standards had been lowered. The pre-trade Knicks were two games over .500, and there are times they’re recalled as fondly as the Riley Boys. The post-trade Knicks were 14-14, sometimes looked like world-beaters and sometimes looked like they’d been introduced five minutes before tip-off, but the people still watched intently.

So, yes, there was a sense of renewal this year, of rebirth.

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“It was a great run for us,” said Amar’e Stoudemire, who played admirably through a barking back and was a model of excellence from the jump. “It’s been a great year from start to finish. The Knicks are back — that statement is true. I think the league knows it. Players are looking at the Knicks and saying, ‘I want to be a part of that team.’ ”

It was a year-long honeymoon, but that’s done. The Knicks can’t afford to think of progress from this point forward incrementally. Despite how the season ended for Stoudemire, everyone knows he won’t remain physically intact forever. For now, they have what any team would envy: two stars, two go-to players, two extraordinary talents.

But if the last two months have proven anything, it’s that they need help, need a beefed-up supporting cast, need to be stronger up front and deeper on the bench if they want to compete with Boston and Miami and Chicago in their own conference. Often this year D’Antoni talked of his “young” team, but that no longer washes.

The future is now. Today.

“They’ll be good,” Celtics coach Doc Rivers said of the Knicks. “They have two great players. At the end of the day, they’ll be formidable going forward.”

At the end of this day, the Garden chose gratitude over greed. The Celtics were running out the clock, the Knicks were letting them, and the people rose to their feet and started to applaud and then cheer and then give them a lovely, loud parting gift.

They enjoyed their feisty upstart Knicks. And starting today, they will demand something else — something bigger, something better.

And should. Even as time runs out on this season, it begins anew. The Knicks are on the clock.

michael.vaccaro@nypost.com