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Looking at Duke's perimeter options

And tying it all in a pretty bow.

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Jim Sumner
May 28, 2026
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John Blackwell withdrew from the NBA draft last week.

No surprise. Expected all along. Barring something very unexpected coming through the transom, Duke’s 2026-’27 roster seems set.

What did Blackwell learn in his NBA tryout?

Well, he needs longer arms. He measured 6-3.25 without shoes. Colleges measure players with shoes on, the NBA with shoes off. No surprise there.

But Blackwell also measured with a 6-2.25 wingspan.

It is very unusual for a player to have a shorter wingspan than height. Not what NBA teams are looking for. Incoming Duke freshman Bryson Howard is about the same height as Blackwell and has a wingspan very near seven feet.

Doesn’t mean Blackwell can’t be an outstanding college player.

Because he already is. He joins a perimeter rotation that includes Caleb Foster, Dame Sarr, Cayden Boozer, Deron Rippey, Jr. and Howard. Even if we consign Sebastian Wilkins to the 4 and Jacob Theodosiou to the deep bench, that’s still a lot of talent for 120 minutes at the 1 through 3.

How does this all play out?

Some thoughts, starting with Caleb Foster.

He’s not Duke’s most talented player. But he’s a fan favorite and for good reason. We’ve all seen the photo of young Caleb Foster wearing a Duke shirt. He’s fought through numerous foot injuries, surgeries, rehabs, slumps, benchings. And he’s still standing. His performance against St. John’s should become a permanent part of Duke lore.

And he’s a pretty good player. He can knock down an open 3, get to the rim, facilitate for his teammates, rebound and defend at any one of the three perimeter positions.

Duke has had lots of seniors, even grad students, in recent years. Sion James became a second-round NBA draft pick and NBA rotation player. Maliq Brown became the ACC Defensive Player of the Year and Sixth Man of the Year.

But neither began their careers at Duke. Jordan Goldwire and Joey Baker played four seasons at Duke but elected to use their bonus Covid year elsewhere.

We have to go back to Jack White and Javin DeLaurier to find an analog for Foster, four years at Duke and nowhere else. Foster is better than either. Maybe back to Grayson Allen?

Foster likely will play more off the ball this season, likely come off the bench. But Duke has a long tradition of valuable sixth men, starting with David Henderson in the mid-1980s and including Marty Clark, Corey Maggette and Jon Scheyer. Billy McCaffrey made the 1991 All-Final Four team coming off the bench.

Scheyer started one game as a sophomore in 2008 and averaged 11.7 points per game. He knows how this works.

Why might Foster not start?

Back to Blackwell. In a way he’s as much of a unicorn as Foster.

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