PROSPECT HEIGHTS — Jay-Z is in a Brooklyn state of mind.
The rap superstar drew 20,000 fans and a flock of celebrities to the official launch of the Barclays Center with a sold-out concert Friday night.
"It's the original Brooklyn boy back in Brooklyn," said Marisaa Santella, 24. "I feel like this is a pretty big moment."
The long-awaited arena — hailed by some as a revitalizing game-changer for Brooklyn and slammed by others as a traffic-generating behemoth — lit up Friday night as fans streamed through the rain toward the main entrance at Atlantic and Flatbush avenues.
"Look how many people are out here tonight — this is amazing," said basketball legend Magic Johnson, who added that he looked forward to seeing the NBA's Brooklyn Nets take the floor of their new home court in the Barclays Center later this fall.
"This arena means something to everybody," Johnson continued, "not just the people who's gonna play in it in the NBA and all the great entertainers, but it means something for the people who live here in Brooklyn. That's what I'm excited about."
Other famous people came out to celebrate the arena's opening Friday night included TV personality Star Jones, hip-hop artist J. Cole, actor Al Roker, Giants wide receiver Victor Cruz and Knicks center Tyson Chandler.
James Mays, a newly signed Nets player, said he couldn't wait to play in the arena next month — but he was already thrilled to see the excitement around Jay-Z's opening concert.
"New arena, you got Jay-Z coming out, you know he's gonna bring out a lot of fans and new artists," Mays told reporters. "I think it's going to be historic."
Some concertgoers Friday night were taken aback by the strong security presence, which included guards in military uniforms carrying assault rifles.
"It's a good thing that we're safe, but it's a little awkward," said Allana Lopez, 23, who is such a devoted Jay-Z fan that she snapped up tickets for two of his Barclays Center performances the first week they were available. "Why do we need all this tight security? It's unnecessary."
In addition to legions of police officers and private security workers, 19 pedestrian managers from Sam Schwartz Engineering were on hand to supervise the flow into the arena.
Although many of the Barclays Center's Prospect Heights neighbors worried about traffic jams, most of the crowd appeared to arrive on foot Friday night, and traffic on the surrounding streets did not appear worse than usual.
Most passersby praised the Barclays Center Friday night as a boon to Brooklyn's future, but they were split on the structure's show-stopping rusted metal facade.
"It's kind of an eyesore," said Jerard Ingram, 42, a lifelong Bed-Stuy resident who was not seeing the Jay-Z show. "But as far as the economy and jobs for Brooklyn, it's a win…. I'm all for it. I don't have to go to Manhattan anymore to take my daughter to the circus or other shows. I'm glad we have a venue of our own."
Nearby on Dean Street, groups that opposed the controversial use of eminent domain to clear space for the Barclays Center and the future Atlantic Yards development held a screening of "Battle for Brooklyn," a documentary chronicling the project's history.
"I think it's a beautiful building and an incredibly corrupt process," said Michael Galinsky, the documentary's photo director. "I love basketball. That doesn't mean we should ignore how things come to be."
The Barclays Center is just the first piece of Forest City Ratner Companies' $5 billion Atlantic Yards development plan, which is also slated to include new apartment towers.
Jay-Z will perform seven more special launch shows through Oct. 6, and other headliners this fall include Barbara Streisand Oct. 11 and 13 and Justin Bieber Nov. 12.
The Nets are scheduled to play their first game in the arena Oct. 15, a preseason match against the Washington Wizards. Their first regular season game in the arena will pit them against their new crosstown rivals, the Knicks, on Nov. 1.
"It's beautiful," said Billy King, general manager of the Nets. "Tonight is about Jay, but I think when we open up on our first game it's going to be a great night."