"It's like any injury, you never know for sure," Kiffin said. "All of a sudden, something starts coming back and it's a body. You can't be exact about your evaluations all the time and so at one point we thought he was feeling better and then he'd have a setback because he's pushing himself further.
"This would be disappointing to have another week without him but we've done it before and if we're forced to do it again, we'll do it again."
Derrick Burgess has not played since injuring his right calf in the fourth quarter of Oakland's 23-20 overtime loss to Denver on Sept. 16. He has just one tackle and is without a sack after recording 27 sacks over the last two seasons.
Burgess did work out Wednesday but backed off after aggravating his injury.
"We were trying to go slow with him," Kiffin said. "Then he was starting to feel better and now we've had a setback the last 24 hours."
Two days after saying he expected Pro Bowl defensive end Derrick Burgess to start against San Diego, Raiders coach Lane Kiffin backed off of his comments after Burgess wasn't able to finish practice Monday.
Two days after saying he expected Pro Bowl defensive end Derrick Burgess to start...