Feb 1, 2025; Durham, North Carolina, USA; Duke Blue Devils forward Cooper Flagg (2) reacts after scoring in the first half against the North Carolina Tar Heels at Cameron Indoor Stadium. Mandatory Credit: Zachary Taft-Imagn Images Zachary Taft-Imagn Images

Cooper Flagg's high school coach reveals favorite detail about future Maverick

Originally posted on Dallas Mavericks on SI
By Austin Veazey | Last updated Jun 24, 2025 4:10 PM ET

Just one more day remains until the Dallas Mavericks will officially select Cooper Flagg with the first overall pick of the 2025 NBA Draft. It's been a long-awaited moment for the Mavericks since they won the NBA Draft Lottery on a 1.8% chance, and they've been excited about the opportunity of adding Flagg throughout the entire process, not even entertaining a trade or any other prospects.

But before Flagg was starring for Duke, he and his twin brother left Maine to play for Montverde Academy, arguably the most prolific basketball academy in the country, where they won a national championship.

Flagg's coach at Montverde, who just left for SPIRE Academy, was on the "Ryen Russillo Podcast" on Tuesday and gave some insight to his former player, who is set to become his fourth first overall NBA Draft pick from his tenure as a coach.

"He's not overly talkative in the public, I think he can be misunderstood. I think he's very humble for his success level and very willing to get better. He's very coachable... I think he's had great training, great support community in Maine... but what I Iove about him is you can be very honest with him about his weaknesses, and he's very accepting of that...

"He's growing and growing his game. To me, he's probably going to be a 19, 7, and 7; 22, 10, and 8, and kind of like Cade Cunningham, who we had, and all of a sudden he's averaging 27, 11, and 9, and just incredibly impactful. But he's also very liked by his teammates, he knows how to interact and get along with people, and his teammates, they all like him, and they all respect him because he works really hard."

He says he never even got a call from Dallas about Flagg because everyone just knows the type of guy he is, and they're not worried about it.

Flagg will soon join Kyrie Irving (his future Mavs teammate), Cade Cunningham, and Ben Simmons as players coached by Boyle who went first overall in the NBA Draft. He's also coached Scottie Barnes, Joel Embiid, Al Harrington, Samuel Dalembert, Derik Queen, RJ Barrett, and many other players who would go on to make the NBA.

This article first appeared on Dallas Mavericks on SI and was syndicated with permission.

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