Luck, who starred at nearby Stanford where he played under 49ers Coach Jim Harbaugh, completed 18-of-27 passes for 164 yards and didn't commit a turnover for Indianapolis (2-1).
On defense, Indianapolis held San Francisco quarterback Colin Kaepernick to just 150 yards on 13-of-27 passing, forcing an interception and a lost fumble.
Frank Gore ran for 82 yards on 11 attempts for the 49ers (1-2).
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