Ex-NBA Champion is a believer in Mavericks rookie Cooper Flagg

As Cooper Flagg is about a month away from his debut, one former champion is bought all the way in.

Jul 12, 2025; Las Vegas, NV, USA; Dallas Mavericks forward Cooper Flagg (32) looks on during the first quarter of their game against the San Antonio Spurs at Thomas & Mack Center. Mandatory Credit: Candice Ward-Imagn Images | Candice Ward-Imagn Images

Cooper Flagg is a little over a month away from making his highly anticipated NBA debut for the Dallas Mavericks. He enters the league as the most hyped American prospect since Zion Williamson in 2019, and NBA fans are excited to see him in Dallas, where he'll be able to step into the massive shoes left by Luka Doncic.

Among those who are ready to see the 18-year-old in action is former NBA champion Matt Barnes. He caught up with Kevin Gray Jr. of DLLS Mavs at the Terence Crawford-Canelo Alvarez fight in Las Vegas, where he revealed he watched Flagg in AAU and was impressed even back then.

“I absolutely love Cooper Flagg," Barnes started. "I coach my kids in AAU, so I got to see him for one season, and what stood out to me the most was his effort and energy. I came from an era where effort was necessary, and he has one of the best efforts I've seen on both sides of the ball.

“What excites me most is his defensive prowess. He can be someone in today's NBA who can guard any position. On offense, he is freakishly athletic and continues to improve his jumper. I am really excited for his future.”

"This team is a LOADED team."

All The Smoke's Matt Barnes says that, if healthy, the Mavericks are good enough to represent the West in the NBA Finals@KevinGraySports | @allthesmokeprod | #CaneloCrawford | @netflix | @DLLS_Sports pic.twitter.com/fQIjtwu6gj

— DLLS Mavs (@DLLS_Mavs) September 12, 2025

READ MORE: Cooper Flagg's trainer details main focus ahead of Mavericks debut

Matt Barnes Not Sure the Mavericks Deserve Cooper Flagg

Although Barnes is a big fan of Flagg, he's skeptical about whether the team deserves to have him or not.

"Somehow, someway, that was a favor because Dallas wasn't a bad team; they shouldn't have been the No. 1 team to get the pick," Barnes said on the "Big Boy's Hangout" podcast. "On the flip side, it's so important as a young player to go to an organization that's stable, has veterans, has great leadership. The ownership of the Dallas Mavericks has to show that now, their job is not to f–k it up because they've done some questionable things in their short time [since] taking over from Mark Cuban."

Flagg will have a lot on his plate this season on a team that is oddly constructed, and the Mavericks have to at least make the playoffs this season. Otherwise, there will be some uncomfortable conversations in that building.

READ MORE: Luka Doncic reveals why he 'didn't know how to react' to Mavericks-Lakers trade

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