Ahmad Brooks misses practice

SANTA CLARA, Calif. -- While the San Francisco 49ers' two biggest injury question marks practiced Wednesday, a key defender was unexpectedly absent.

Outside linebacker Ahmad Brooks, a Pro Bowl selection, did not practice because of an illness, the team announced. A source said Brooks' absence does not appear to be serious at this point.

Cornerback Carlos Rogers and fullback Will Tukuafu did practice on a limited basis. It's a sign that, barring a setback, both players should be able to play in the NFC Championship Game at Seattle on Sunday.

It was Rogers' first practice since he suffered a hamstring injury in Week 17. Perrish Cox took over as the nickel cornerback in the playoff wins over Green Bay and Carolina. 49ers coach Jim Harbaugh said how much Rogers will play will be determined on the practice field this week.

Tukuafu hurt his knee Sunday at Carolina. He has said he plans on playing. If he can't, Anthony Dixon will share time with rookie tight end Vance McDonald at fullback.