Going Small (running)
1. D. Williams
2. R. Beaubois
3. M. Thornton
4. J. Green
5. J. McGee
Thoughts?
You are not going to be able to play Jeff Green (PF) + JaVale McGee (C) together. They are too deficient defensively (for now, at least).
That lineup would also get massacred on the backboards 2 through 4 (SG, SF, PF). The wing defense (Deron, Thornton) is very poor too.
That lineup would get outplayed with regularity. Your team won't be able to stop anyone, can't rebound and won't score enough to make up for it.
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If you play Jeff Green at center you need a legitimate defensive presence at the five alongside him. Preferably one with a physical presence. Not a finesse defender who gets lost repeatedly on team defense and cannot defend his own man (McGee). Brendan Haywood can fill this role. Play him and four quick players for your running lineup.
To get any type of value out of Green defensively at the four position you'll need big wings (height, length, physical strength -- they'll be switching onto PFs, strength is important) alongside him allowing you to switch repeatedly on defense. Deron Williams is a big strong (physically) point guard so he can switch on several matchups too.
That means small backcourts (Deron + Roddy) are to be kept to a minimum (only when other team is small in backcourt) while Green is at the four and that Marcus Thornton cannot play the three (strictly a two guard, too one dimensional to switch positions competently).
Otherwise, Green's limitations defensively at the four will create too large a negative. He is an atrocious man-to-man defender and is too small to provide adequate team defense in the paint. His transition defense, pick and roll defense and perimeter defense are solid to very good. Add his ability to switch and your team defense can become very active while he is at the four.
Long defenders, strong defenders, guys who can rebound the basketball. Must haves for Jeff Green to play the four.