Team trainer Rick Buckholder told reporters that quarterback Alex Smith has a lacerated spleen and will not play Sunday.
Smith took a shot to the abdomen in last week's loss to the Pittsburgh Steelers. The quarterback didn't feel right, but practiced earlier this week before the laceration was detected.
"It certainly wasn't something that prohibited me athletically, I didn't feel like it was muscular, just discomfort," Smith said Friday. "Nausea coming and going, I knew a bug was going around, I thought maybe it was that. I practiced both days, I felt great athletically running around and throwing. I had this constant deal going on and then doc urged me to go get the test. I was pretty reluctant yesterday. I said I was alright and they pushed me to get checked out and I got the call that I had the laceration on there and it was enlarged."
In last season's finale, Daniel went 21-of-30 passing (70 percent) for 200 yards and one touchdown pass in the 27-24 loss to San Diego.