Joel Embiid has yet to make his NBA debut, but after two years of watching him rehab from foot injuries and develop on the court, Brett Brown has a clear picture of the big man’s role on the Sixers.

“He needs to be the crown jewel, the centerpiece to our defense,” Brown said Thursday at his annual preseason luncheon with the media.

Over the course of his rehab, Embiid has been wowing with videos of himself knocking down three-point shots and dunking. Brown, though, envisions him making an impact on the other end. He believes Embiid’s 7-foot-2, 276-pound presence is best utilized at the basket. Last season, the Sixers ranked last in the league in rebounds (41.2), opponents’ rebounds (47.6) and rebound differential (minus-6.4) per game.

“I think he's a rim protector,” Brown said.

Brown expects Embiid to be ready for the start of training camp on Sept. 27 and the preseason opener on Oct. 4 against the Celtics. Embiid and the Sixers have been waiting since draft night 2014 for Embiid to play his first game. Given the long recovery process, which took Embiid as far as Qatar, the Sixers are continuing to follow their carefully mapped out schedule. There will be restrictions for Embiid’s playing time, which are to be determined.

“I think we all know that there are parameters coming,” Brown said. “We all know that less is more. We want to walk him down in a very responsible, thoughtful way, where we continue to deliver him to the court in a calculated way that doesn’t jeopardize anything with what we just spoke about — the investment that he has made, and we have made, in the past few years.”

Brown knows firsthand the value of healthy bigs. Brown, who spent over 10 years in the Spurs' system, has shared stories of his championship-winning days with David Robinson and Tim Duncan (see story). He has told Embiid about the widespread effects of a defensively-savvy presence in the paint.

“I learned in my first year going to a team that had Duncan and Robinson behind your defense,” Brown said, “it allowed the perimeter defenders — Mario Elie and Steve Kerr and Avery Johnson-type guys, Sean Elliott — that ... you could be a little more physical. Sometimes if they beat you, you had the luxury of that behind them. So there was a bravado, there was a toughness, there was an aggressive philosophy we could put on the ball.”

From draft night to training camp, Embiid has been transforming his body to become NBA-ready. Brown also has seen changes in the 22-year-old’s personality. Two rehab processes later, Embiid has taken on a new outlook.

“Joel’s frustration has been documented his first year with us when he was out,” Brown said. “He is a 7-foot-2, young kid, all balled up, can’t play, trying to figure it out, what does this mean, trying to be professional with rehabilitation and recovery, and sometimes frustrations got the better of him.

“The growth of Joel Embiid as a person, then as a player, is important to me. I think that the path that has unfolded sort of organically, with the injury, the setback, and now here he is, I think we could look back and say in an inverted, twisted type way, it has provided him a layer of growth. I think he sees the world a little bit differently in relation to taking things far more seriously, professionally, etcetera. I see a more mature Joel Embiid today.”

Embiid was one of many players at the Sixers' practice facility on Thursday putting in work before training camp. Among those was fellow big Jahlil Okafor, who rolled an ankle last week. Brown expects Okafor, who has recovered from right knee surgery, to be ready for the start of camp.