While I agree the Phillies have been rather injury-stricken in the infield, it has been reported the Phillies basically need to trade for every position.
In the past week, they have been rumored to have expressed interest in Heath Bell, a relief pitcher; Juan Rivera, one particular outfielder although they have looked at others as well previously; and now they are looking at infielders.
What are the Phillies going to do?
I think that the most pressing need is still in that gap of a right-handed hitting outfielder.
Raul Ibanez has been having a difficult year in left field (according to FanGraphs, he has the lowest Wins above Replacement of any outfielder in Major League Baseball this season), and Domonic Brown has been somewhat streaky this season.
I am not saying the Phillies should necessarily replace either of these two right now, but I do think a right-handed bat in the outfield would help relieve the problem the Phillies have against left-handed pitching.
While the Phillies are having injury problems in both the bullpen and the infield, those positions will be able to heal and be solid again.
Chase Utley is on his way to recovery, and Placido Polanco will hopefully be able to shake off his back spasms.
The missing pieces of the bullpen are due to come back soon as well, and in the meantime the bullpen has been solid, anyway.
Obviously, there is always room for improvement, but I think that the Phillies should not worry as much about the infield.
The best move the Phillies can make right now is to keep focused on improving the outfield with a right-handed bat.