He's not gonna be GOOD on defense, but he has long arms and at least tries to be in the right place and he's already solidly 230 with room to get stronger. He really can't move when you go at him, but he at least has the instincts to get a few steals and is long enough to at least present some obstacle at the rim. I'm actually a bit more worried about his offense, if you can't score at all in the NBA, even the best passer in the world is gonna have his impact limited (Rubio!), so he at least needs to shoot well enough so that defenders don't sag off him and fuck up the entire offensive flow.