The issue is STs and I don't recall Green being on STs.
So in that case, I can't see keeping 4 RBs. Rather I seen Green on the PS.
Further, I'm just not so sure about keeping a FB. Either McVay is keeping the FB under wraps, or Rogers simply is not as good as hoped for. I can think of a half dozen guys at various roster positions that are simply better than Rogers. Perhaps PS, but I'm doubtful. To me, keeping a guy on the PS for a FB is kind of a waste unless you think you have something special. He doesn't look special to me.