Recently signed Colts K Matt Stover converted all of his four field-goal tries in Sunday's 18-14 win over San Francisco.
With rookie RB Donald Brown (shoulder) inactive, Joseph Addai averaged just 3.1 yards per carry as Indianapolis' every-down back.
Colts WR Reggie Wayne (groin) admitted afterwards that he didn't think he'd be able to face San Francisco early in the week, but dominated with 147 yards and a touchdown on 12 catches.
Colts DE Dwight Freeney has at least one sack in eight straight games, matching Robert Mathis' franchise record.
The 49ers started Sunday's game in a two-receiver set, with Michael Crabtree and Josh Morgan out wide and Isaac Bruce on the bench.
49ers CB Shawntae Spencer was the victim on Addai's 22-yard touchdown pass to Wayne.
49ers SS Michael Lewis returned from a concussion Sunday to post five tackles and force a fumble by Colts TE Dallas Clark.
49ers QB Alex Smith played well despite the loss, with his only interception coming on a ball that went off Crabtree's hands.