Coach Scott Linehan also said Monday that running back Steven Jackson, sidelined by back spasms in the first half after a strong start, has a bulging disk. But he said the injury is treatable and was optimistic Jackson could be back in the lineup without missing a game after the Rams' bye this weekend.
Tackle Orlando Pace was lost for the season with a shoulder injury in the opener and guard Mark Setterstrom also is out for the year with a knee injury.
Incognito missed the first four games with a high ankle sprain he sustained during the preseason. He was injured during the first quarter Sunday when Linehan said his kneecap popped in and out on a play when his leg was in an awkward position.
"It's a somewhat lengthy recovery time," Linehan said.
Copyright 2007 by The Associated Press.