Cooper Flagg hasn’t played a regular-season game yet, but the Dallas Mavericks already expect him to act like more than a rookie.

Anthony Davis, entering his first full season with Dallas, said the teenager’s defensive tools are obvious. What matters now, Davis emphasized, is Flagg finding his voice.

“Man, he has a lot of talent on both ends of the floor, but defensively, he’s going to shine,” Davis said. “We’re going to put him in situations where you have to guard maybe the best wing, to have to guard Kevin Durant or Jimmy Butler or these guys. We have enough confidence in him to go out, send him out there and be able to guard those guys.”

That kind of responsibility rarely falls on a first-year player, but the Mavericks drafted Flagg No. 1 overall with the expectation that his defense could change games immediately. Training camp practices have underscored those expectations.

During one drill, Davis noticed hesitation from Flagg in taking charge.

“He can block shots, he can jump, he can rebound, he can defend one through five,” Davis said. “But I told him in practice today, we’re doing a drill, and you know, he was hesitant about kicking the guy out. And I said, ‘You’re very great defensively, where you have the ability to grab him and throw him and tell him to get to his position.’”

The veteran made it clear that Flagg’s responsibility isn’t limited to effort alone.

“And we gotta be able to do that, not just because he’s a rookie, but because we want to win,” Davis said. “He has the talent to do so. He can cover a lot of ground, force guys to get beat. He can cover up for us.”

Dallas is in the middle of a dramatic transition after the February trade that sent Luka Dončić to the Los Angeles Lakers and brought Davis to the Mavericks. Flagg’s arrival as the No. 1 pick added a second layer of change, one the franchise is framing as the beginning of a new era.

Flagg has already drawn praise from teammate Klay Thompson, another offseason addition, for the way he handled early workouts. Davis’ message has been more direct: talent won’t be enough, and confidence can’t wait.

The challenge ahead for Flagg is enormous. The Mavericks envision him matched up with elite scorers across the Western Conference, asked to cover ground, close gaps, and take on assignments that even established veterans might find daunting.

It is an early trial by fire for a player many view as Dallas’ next cornerstone. Whether Flagg can live up to that billing in his rookie season is uncertain, but Davis’ insistence is that he already has the tools — and now needs to use them without hesitation.