Valanciunas recorded a double double in his first Euroleague game ever. And he started that game on the bench. Yeah, he is impressive. But he commits a lot of fouls, maybe it's just a lack of experience, it's his very first season in such a high level.
But in the NBA, if you talking about defensive centers, you think about the guy like Wallace, or howard. Yeay, Varejao is one of the best defensive players, but he still can't stop Dwight Howard or Shaq.
Valanciunas is all around player, not defensive stopper. He is master of the pick n roll player, good awareness, shot blocking. Big time potential but not NBA ready.
And we talking about late second rounder, not a top10 pick. Boban is terrible, but he is 7'3, as a late second rounder, he is not that bad...