For the 49ers their health has become a greater concern than their preseason performance. They just need to make sure they have enough healthy bodies to keep their key starters out of harm's way. More than 20 players missed their preseason opener vs. the Denver Broncos with injuries, and that number could rise Saturday when they face the Raiders.

Bitter rivals clash as the San Francisco 49ers and the Las Vegas Raiders go head-to-head in Week 2 of the NFL preseason today.