How long will the honeymoon last?

The arena was packed to capacity, similar to what was seen just a night earlier in midtown Manhattan when the other team in town decided to host a basketball game. Except this wasn't Manhattan. Or the Bronx. Or Staten Island, Queens or anything like them.

"It's Broooook-lyn. ... Broooook-lyn," guard Joe Johnson sang while bobbing his head, mimicking echoes serenaded by the sellout crowd inside the Brooklyn Nets' brand-new home, Barclays Center, on Saturday night.

"I loved hearing it. We all did," Johnson said. "The thing is, it had me hyped, and I wasn't one of these guys who played with this team in New Jersey the last couple of years. So if I'm hyped, imagine how the rest of this team is feeling."

There's no need to imagine any longer.

Dressed in their sparkling white jerseys, with "Brooklyn" emblazoned in black across their chests, the Nets finally discovered what pomp and circumstance really is after slapping high-fives with Jay-Z, then responding the way any capable team should. Sparked by a 27-point outburst by center Brook Lopez and tough defense when it counted most, the Nets didn't just beat the Toronto Raptors 107-100 ...

"We took a step towards establishing a home base for ourselves," coach Avery Johnson explained. "This type of atmosphere is that sixth man, the kind capable of inspiring its home team and making life uncomfortable for visitors. That's the way it's supposed to be. That helps you win games. And I have no doubt that Brooklyn will handle its end of the bargain."

Lord help the Nets if they don't handle their end.

Brooklyn is nothing like the home the Nets occupied for years off Exit 16 on the New Jersey Turnpike. Apathy and indifference will not exist at Barclays Center. Neither will a tolerance for ineptitude nor years of futility. Because while the Nets are relevant again, by sheer virtue of the fact that they've returned professional sports to the borough of Brooklyn for the first time in 55 years, such gratitude will fade if their production deteriorates.

"Like I said, it's Brooklyn," Johnson reiterated. "We saw those folks out there. We know what they expect."

And being better than the New York Knicks will suffice as one of those expectations ... which, by the way, isn't so far-fetched.

There's no definitive No. 1 and No. 2 in basketball in this city right now, and it's not just because Lopez's output nearly matched the 30 points Carmelo Anthony put up on Friday night versus LeBron James, Dwyane Wade and the Miami Heat.

There are many reasons for the suspense and intrigue surrounding the inevitable "Who's better: Knicks or Nets?" question, and it's not going away anytime soon.

For every moment Melo explodes, the argument can be made that it's offset by too many occasions in which he'll be isolated on the wing, nullifying the Knicks' ball movement, just as he did on a few occasions against Miami. There are also the questions regarding how often Steve Novak will hit seven 3-pointers or Jason Kidd three treys, or about how many times the Knicks are going to be able to drop 19 shots from beyond the arc, not to mention maintaining their defensive tenacity with the league's oldest squad.

Except, that last example is about the only part where the Knicks get a bit lucky pertaining to bragging rights in this city.

Engulfed with adulation leading up to tipoff, the Nets nearly nauseated their 17,732 fanatics with the kind of performance reminiscent of a team that ranked 21st and 29th in defense over the past two seasons.

The Nets gave up 62.5 percent shooting from the field in the first quarter and 66.7 percent from 3. In the end, they surrendered 28 points to Kyle Lowry and another 25 to DeMar DeRozan -- highlighting the reality that they'll never be better than the Knicks if they don't learn to stop folks.

"We were pretty bad defensively in that first quarter," Johnson deadpanned. "I won't deny it. But we turned it around from there, and our reserves actually led the way."

Whether that can continue remains to be seen. Even with Deron Williams (19 points, 9 assists) and Joe Johnson (14 points), no one's about to mistake the Nets as a stellar defensive team.

For one night, however, it really wasn't necessary.

"The truth is, we're still learning who we are and what we're going to be," Lopez said. "I'm excited as I can be, because I believe we're going to be good. We've got all the incentive in the world to be good. We're here in Brooklyn, with this arena, this crowd. They're hungry. We're hungry. What more could you ask for?"

Give it time, Brook.

Brooklyn will figure out something.

Eventually, of course. Just not Saturday night.