Josh Smith, Rondo and Green would be a good foundation. Still need a center to anchor the defense. Perhaps KG could stick around and show the young man what it means to be a Celtic. My only fear is that Smith would drag Rondo's game down; but would more likely be the other way round.
We already have a center. Sullinger.
Have you not seen what this kid brought this year? He is only going to get much better. When you have a guy that can neutralize Tyson Chandler, than you have someone that can play center.
He is not a true center, but in today's nba , you don't really need one. Sullinger's biggest weakness is shot blocking, but Smith if we got him could do plenty of that