According to Jason La Canfora of CBS Sports, Cardinals running back Rashard Mendenhall has a sprained knee and is expected to be ready for week one.
For those asking about Mendenhall's health in light of AZ's openness to deal Ryan Williams, its a minor knee sprain. should be back week 1
— Jason La Canfora (@JasonLaCanfora) August 26, 2013
The knee Mendenhall injured is the same one he had ACL surgery on almost two years ago.