Teams play twin towers, still.
The thing about Leonard is that the scouting report on him is that he's big but fast and agile, not too big and too slow.
I think he's best suited at C, though.
http://www.draftexpress.com/profile/Meyers-Leonard-5756/
As we've mentioned before, Leonard's intrigue starts with his excellent physical profile, as he possesses the ideal traits for a prototypical NBA center. Standing 7-feet tall with a long wingspan and a developing frame that should continue to fill out nicely in time, Leonard moves very fluidly for a player his size, running the floor well and showing solid explosiveness, vertically and laterally.
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As we've mentioned before, Leonard's physical tools make him a rare and very intriguing prospect defensively, especially as his frame continues to fill out. He did a better job denying deep post position this season and generally displayed a good effort level, which combined with his size and length, makes him an effective one-on-one defender on the interior, as players have trouble scoring over the top of him.
His excellent agility for a player his size should also help him defending pick-and-roll sets, giving him the ability to hedge and recover quickly. A big key for him defensively will likely the mental side of things and how well he can focus and bring consistent energy on each possession and pick up on team defensive concepts.