Jaylen Brown drives past a Spurs defender, accelerates toward the paint and extends his left arm to finish at the rim. Once known as a mostly one-handed player, left-handed plays have now become routine for him. Ask him about the development, though, and he may tell you his growth is not confined to one skill or another. He is a basketball player, he stresses. He tries to improve every part of his game each season.



What you see is what he does, but it is not necessarily what he is — and it’s definitely not what he will be. Brown considers that an important distinction. So much goes into a player’s productivity: the system he’s in, the teammates around him, the chances he receives. If you see Brown make one type of play regularly now, he has been honing that craft repeatedly behind the scenes. The idea, he says, is to prepare enough that he does as little thinking as possible while on the court.



Brown has not always been able to play with a free...