Showdown between LaMelo Ball and Zion Williamson in AAU game in Las Vegas draws massive crowd

NBA stars, Hall of Fame coaches and thousands of spectators showed up to the biggest attraction in Las Vegas to see two top-10 high school basketball prospects clash on the same court.

Junior point guard LaMelo Ball and the Big Ballers Brand took on senior Zion Williamson and his SC Supreme team in Wednesday’s Adidas Summer Championships game at the Cashman Center in an oversold exhibit hall.

In what was by all accounts a chaotic scene, fans stood six and seven deep to watch. Adidas representatives estimated that between 3,000 to 4,000 spectators were present, with another 1,500 outside. Officials ordered doors blocked and a police barricade was set up outside the arena an hour before tipoff because of fire safety concerns.

Organizers were worried that the game would be canceled due to the massive turnout, but local police gave event organizers the green light only a minute before game time.

NBA stars Damian Lillard, Andrew Wiggins, Jamal Murray, Thon Maker, Eric Gordon, and Lakers rookie and older brother Lonzo Ball came to see LaMelo and Williamson square off.

College coaches in attendance couldn’t believe what they saw.

“Unreal. Never seen anything like it,” Hall of Fame and Kansas coach Bill Self told ESPN.

“It reminds me a little of LeBron [James] games,” Gonzaga coach Mark Few said.

James showed up at the venue Wednesday but was turned away due to the already overwhelming crowd size.

SC Supreme defeated the LaVar Ball-coached Big Baller Brand squad 104-92 but spectators got what they wanted: a showdown between two top-10 recruits. LaMelo scored 31 points while Williamson finished with 28 points.

“They’re going to have to get a bigger venue,” LaVar, the brothers’ father, told ESPN after the game. “When the Big Baller Brand come to town, better get something big.”

Twitter: @edmgonzalez

eduardo.gonzalez@latimes.com