I actually think if Gay is playing, they should just start him. Why wait? I get the "he hasn't practiced yet" argument, but it's not like he's going to learn everything in one practice anyway. The sooner you start working him into game situations the sooner chemistry develops.
I can't see the offense being a reason to sit him, and while he might not know some D principles, I would just say don't play zone when he's out there, and he should be able to manage the rest of the time if the team communicates...and if they don't our D will probalby be sucking anyway.
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