Eric Mangini sits with the unenviable task of leading a defense that has seen major pieces exit the building.The lo ses have been recounted times this offseason, but the most recent exit is likely the one that stings the most: . "He's not a guy you can just replace; he Jeff Green Jersey 's got a unique skill set," Mangini said, . "But one of the things we've focused on defensively is building flexibility in terms of what we can play." The leaves a huge pa s-rushing void that Mangini needs young players like to fill -- and rookie will also take outside linebacker reps. One option the defensive coordinator could take to manufacture a rush is blitzing, which the Niners were working on even before releasing Smith last week. Mangini has "done more blitzes this offseason than we've seen in the previous six combined," left tackle said. Regardle s of how he goes about solidifying his defense, Mangini knows a player like Smith won't be walking through the door to help him out. The latest Podcast Karl Malone Jersey