Justin Smith among NFL's most indispensable defenders

Daily 49ers blog for NBC Bay Area website: Justin Smith is lifting weights again and reportedly on track to be ready for work on Day 1 of the 49ers' summer training camp. That's good news for the Niners. http://www.nbcbayarea.com/news/sports/With-Strength-Back-Justin-Smith-Will-be-Impact-Player-Again-209667341.html