Inside linebacker Patrick Willis injured his groin while trying to tackle Colts receiver Reggie Wayne at the end of the third quarter and has been ruled out for the game. Michael Wilhoite has replaced him as the "Sam" inside linebacker. Willis' status for the next game automatically comes into question because the 49ers are operating with a short work week. They play the Rams in St. Louis on Thursday.
The 49ers also could be without tight end Vernon Davis, who missed today's game with a hamstring strain. Aldon Smith's status also is unknown. National reports say that the 49ers are strongly considering sending him to a rehabilitation program after he was arrested for DUI on Friday.
-- Matt Barrows