Jeff Capel has a hard time explaining just how smart of a basketball player Carlton “Bub” Carrington is.

There was the play the former Duke star introduced to his team in early December that Pittsburgh didn’t run again until March. Even the veteran coach had to jog his own memory, but the freshman from Baltimore could distinctly recall the action and the name they gave it. Or how Carrington, still 17 when he arrived at campus after a standout career at St. Frances, could defend a doctoral thesis on countering ball screen coverages.

“As talented as he is — and I told every NBA person that’s called me,” Capel said, “I think his greatest gift is his mind. He is incredibly smart. I think that’s the reason why he’s gonna become a really, really good pro.”

Wednesday night, that stage of Carrington’s basketball journey begins from inside the NBA draft’s green room, where the youngest of 24 prospects to accept an invitation will eagerly await NBA Commissioner Adam Silver to call his name to the Barclays Center stage in Brooklyn,