The Red Sox know how to manage “injuries.”
If Lowell goes down, Youk can shift to third and David Ortiz and Chris Carter can share the 1B/DH spots. Or even Rocco could DH at times.
If Daisuke suffers from "arm fatigue." Which could also be labeled as "we are being careful with him because of the the WBC." Then Justin Masterson can shift from the pen to the rotation.
But Theo has built a team that can handle suspensions, injuries, performance issues, more than just about any team in the game of baseball.
And the organization as a whole has built a farm system that has the players to either be quality Major Leaguers, fill temporary holes, or be traded to address any of these "holes."