Peterson scored on runs of 5 and 7 yards, and Brett Favre completed 18-of-24 passes for 232 yards, including a 13-yard touchdown toss to tight end Visanthe Shiancoe.
Marc Bulger, who replaced Kyle Boller in the fourth quarter, threw a 27-yard scoring pass to Donnie Avery and Josh Brown had a 29-yard field goal for the Rams (0-5).
St. Louis has lost 15 straight games going back to last season. The NFL record for consecutive losses is 26, set by Tampa Bay from 1976 to 1977.
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