After taking a look at how the offensive depth hart might look, here's a glance at the depth on the defensive side of the ball:
Left DE - Antonio Smith, Kenny Iwebema, Calais Campbell
Iwebema has been playing the left side but an extended absence by Smith could see Campbell move over.
NT - Bryan Robinson, Alan Branch, Gabe Watson (injured)
Robinson will most likely be the starter against the Niners but he might be the last guy that they want to start as well. Branch might be the best on any given play but you just never know whether you're going to get 100% or 50%. Watson will be the starter as soon he's healthy.
Right DE/UT - Darnell Dockett, Calais Campbell, Kenny Iwebema
Dockett is the stud and and Campbell is the young man in waiting.
Left OLB - Chike Okeafor, Clark Haggans
As long as Okeafor stays healthy he's the man. Haggans has performed well in preseason and he's an experienced veteran, but he's at his best with limited snaps.
Right OLB - Travis LaBoy, Bertrand Berry
LaBoy had a good preseason and won the starting job. He's younger and more explosive but Berry will still see his fair share of snaps when he's healthy.
MILB - Karlos Dansby, Gerald Hayes, Monty Beisel, Ali Highsmith
Beisel's probably the first guy to step in whether Dansby or Hayes goes down and Highsmith's role will likely be special teams unless a couple of injuries strike.
Left CB - Roderick Hood, DRC, Ralph Brown, Matt Ware
The top two spots are pretty set in stone but if somehow they both get injured, it would be a big mess. They would probably decide to move Rolle back down to corner depending on the depth left at safety. Brown is a good special teamer but he's not a starting corner. Ware can play both safety and corner but he's not a starting corner either.
Right CB - Eric Green, DRC, Ralph Brown, Matt Ware
Pretty much the same as above.
SS - Adrian Wilson, Aaron Francisco, Oliver Celestin
Wilson is the obvious starter and there's a big drop off to #2. Francisco's got some experience but he lacks the playmaking ability of A-dub.
FS - Antrell Rolle, Aaron Francisco, Matt Ware, Oliver Celestin
Most depth charts list Ware as the primary backup to Rolle but I still think Francisco would be the first name called if Rolle went down. Ware's younger but still a good, developing player. Celestin is best on special teams but he's a big hitter who will look decent in limited snaps.