Among this year's lottery prospects, Bismack Biyombo(notes) is perhaps the best candidate to be a boom-bust player, with nothing in between. An incredibly athletic player who's only spent a few months at the highest level of Spanish basketball, he could become a defensive force or the kind of player whose lack of offensive skill makes him too much of a liability to stick on the court for extended minutes.
Whatever happens, he'll end up contributing most at the defensive end. But while most players in that role tend to keep their heads down, Biyombo is very confident in his abilities. In fact, he thinks he'll be able to lead the league in rebounding and blocks. From an excellent profile by Scott Howard-Cooper for NBA.com (via EOB):
So, do you believe you will lead the NBA in blocks?
Will you lead the NBA in blocks?
Can you lead the NBA in rebounding?
"Yes, I will."
You will lead the NBA in rebounding?
"Yes. Of course. Hundred percent.
"I don't care how tough people are over there. I don't care how strong they play over there. I know that I'm strong, too. I know that I'm tough, too. I never let people just beat me easy. They're going after me and I'm going to go after them.
It's unclear exactly when Biyombo thinks these events will happen, but let's assume that he's not saying he'll lead the NBA in rebounds and blocks as a rookie (because that would be crazy, not just confident). In truth, that prediction is not wholly out of the question -- Biyombo hasn't been playing organized basketball for very long and nevertheless seems to have a great sense of how to put himself in great position for rebounds and blocks. It doesn't hurt that he's very athletic, of course, but Biyombo has something extra.
What's perhaps most interesting about these claims, though, is that Biyombo is trying to position himself as a player with star potential even though he's not much of a scorer (to put it mildly). Even if unintentionally, Biyombo is suggesting he could become the next Ben Wallace(notes), a player who captures the attention of a broader fanbase even though his offensive game would look bad in the West Coast Conference.
It's tough for a defensive specialist to become a star. But Biyombo might have the highlight-reel capability and capacity for production to do it.