FDB will decide what players he wants to replace after seeing them in training. He knows from players released where some of gaps are.

Joe Ledley - Midfield

Fraizer Campbell -striker

Mathieu Flamini - Defensive Midfirld

Zeki Fryers - Left Back (Cover already)

Sakho - Centre Back

I would therefore think these are areas he looks at covering first. It is possible he will try U23 players I suppose for one of midfield positions and Anderson or Lapado as 4th Striker. But we have no central defender who is ready