Greene said after Friday's preseason game that he hyperextended his right knee, adding that he expects to be okay, the Tennessean's Jim Wyatt reports. Though he expects to be okay, Greene did injure the same knee that he had surgery on during the offseason. His reaction to the injury indicated that it wasn't all that serious, but the context is cause for added concern. The plodding veteran is trying to hold off rookie Bishop Sankey, who already figures to handle a good portion of the work on passing downs.