NBA

Knicks, Nets headed in opposite directions

So it seems we may have to wait a while before we get Lakers-Celtics, Dodgers-Giants, or Army-Navy thriving on either end of the Manhattan Bridge.

It seems the deep passions that burned those first two nights in Brooklyn — when Barclays Center looked and sounded resplendent in its fiery neutrality — will take a while to migrate to Madison Square Garden.

And it seems a rivalry is much better when the participants are evenly matched and equally paired. That is where we stand now, quite clearly, in basketball’s battle for the heart and mind of New York. On the one hand, the ascendant hand, we have the Knicks, now 19-6 after thumping Brooklyn 100-86 last night at the Garden.

And on the other, the Nets, now 13-12, now 4-8 since that overtime victory at Barclays 23 days ago that, they assured us, was just the first march of a sustained assault on the Knicks’ primacy in the marketplace, now 2-8 in their last 10, looking more ragged, more raggedy, and less representative by the day.

Rivalry? Did someone say “rivalry?”

“I don’t know about their struggles and I don’t care about their struggles,” Jason Kidd said with that half-smile of his that has always been reflective of a team residing on the same page. “I care about us, I care about winning at home, I care about playing the Bulls [tomorrow]. What they do doesn’t concern me.”

But it should be a concern for the Nets, who started the season so well, so in sync, who seemed to hungrily buy everything Avery Johnson was selling on both ends of the court. Twenty-four days ago, when they’d emerged from that 96-89 overtime sauna in Brooklyn, the two teams were twinned atop the Atlantic Division at 9-4.

Now, the Knicks have stormed to a six-game lead. Somehow, the Nets have dropped six games in the standings in 19 days. The $98 million point guard, Deron Williams, is griping about the coach’s “system,” even as he’s only occasionally resembled the franchise cornerstone he was supposed to be. The coach has looked overmatched on too many nights, his team playing its very worst every night in the third quarter, when halftime adjustments either take root or blow up.

“We’ve got to get back to the lab,” Johnson said, meaning more practice, more teaching, a few days away from the daily grind of games, and in theory that sounds like a perfect panacea.

“The hype was deserved,” Johnson said of the increased expectations the Nets attracted in the preseason, ambitions that were only rocketed into orbit after their fast start. “But when you get a level of respect, there comes a level of responsibility, too.”

This wasn’t the worst of it, of course; a lot of teams have walked into the Garden this year and fallen under an avalanche of too many 3s and too much Carmelo Anthony. The Nets have lost too many leads, have lost too many games at home, have squandered too many opportunities to establish an identity.

“If you’ve seen us play,” Joe Johnson said, “then you know we’re better than this.”

Well, we thought so, too. But the talent in the room has yet to translate to triumph on the court, not often enough anyway. The Knicks were burdened with expectation this year, too, but have been equal to the obligation. Melo accepted the exact same spotlight as Williams, but where the Net seems shrunken by it, the Knick has rarely shone brighter.

“It’s scary,” is the way Anthony’s coach, Mike Woodson, described it, after a routine 31-point effort on one healthy wheel.

And while the Nets’ descent coincided nicely with the absence of Brook Lopez — who had better still be feeling the effects of his bum foot, because the way Tyson Chandler intimidated him all night was downright terrifying — it isn’t as if the Knicks have been blessed with a robust roster, either.

“Tell them if they need me, I can give ’em good five minutes,” courtside visitor Patrick Ewing said afterward, laughing before delivering the punch line: “Per week.”

The offer was directed at the Knicks. But the way the Nets are headed, they could use a call for all hands on deck, too. Yes, there’s still 57 games left. At some point, it would behoove the Nets to join the fray. The Knicks are a speck in the distance right now. And don’t seem inclined to fall backward anytime soon.

michael.vaccaro@nypost.com