One of the keys to the 49ers defensive dominance in 2011 was the emergence of key players on the defensive line. We already knew Justin Smith was a beast, and he further emerged on the national stage last season. However, almost as important was the emergence of Isaac Sopoaga at nose tackle and Ray McDonald at defensive end. Sopoaga had put together a solid enough season at defensive end previously, but the 49ers elected to gamble with moving him to nose tackle and promoting McDonald into a full-time role. It's safe to say the 49ers were satisfied with that decision.
The depth behind the starting three raises enough question marks though to keep this bubble watch at the forefront in training camp. Ricky Jean Francois has emerged as the primary backup at all three defensive line positions, but the 49ers need to develop further depth. RJF and Ice are both entering free agency after this season, and it is entirely possible at least one of them walks. The 49ers need to be prepared for that, while also knowing they benefitted from a strong run of healthy bodies last season.
After the starting three plus RJF, there are three primary players in this bubble watch: Demarcus Dobbs, Will Tukuafu and Ian Williams. Tony Jerod-Eddie, Patrick Butrym and Matthew Masifilo will be in the mix for practice time, but I'd be surprised to see any of those three legitimately challenging for a 53-man roster spot.
As for Dobbs, Tukuafu and Williams? The 49ers kept all three on the roster last season as they went with seven defensive linemen, although Tukuafu went on injured reserve after a month. Ian Williams retains practice squad, but that will require slipping him through waivers. Although Williams did not play much last season, I am skeptical that the 49ers can slip him through waivers.
We know who the starters will be this year. The more interesting question might be, will anybody do enough to justify letting Sopoaga and/or RJF walk next spring?
Lock: DE Justin Smith, DE Ray McDonald, NT Isaac Sopoaga, DL Ricky Jean Francois
Strong Bubble: DE Demarcus Dobbs, DE Will Tukuafu and NT Ian Williams
Longshot: Tony Jerod-Eddie, Patrick Butrym, Matthew Masifilo