This article was originally published on www.si.com/nba/draft as These Two Questions Will Define Cooper Flagg's Rookie Season.

LAS VEGAS — He missed 16 of 21 shots, including all five attempts from deep, and airballed his first and final shots. And those who saw his NBA 2K26 Summer League debut still came away with a consensus gut feeling: Cooper Flagg is right on pace to be a problem.

After going No. 1 overall to the Dallas Mavericks in the 2025 NBA draft, Cooper Flagg gave props to the reigning NBA champion Oklahoma City Thunder this week.

As much as Cooper Flagg wants to win from day one, six-time NBA All-Star Jermaine O'Neal, who is now the head coach of Dynamic Prep Academy in Irving, Texas, wants Flagg to focus on one thing in his rookie season: development.

The Dallas Mavericks selected Cooper Flagg with the number one pick in this year's NBA draft. Flagg predicted his toughest challenge heading into his first season before his name was called by Adam Silver on June 25. He was introduced by the Mavs two days later and will wear the No. 32 jersey.