The Packers are now 2.5 games behind first-place Minnesota
The Green Bay Packers are now 2.5 games behind first-place Minnesota in the NFC North Division.
The Vikings improved to 5-0 Monday with a 38-10 victory at St. Louis.
The last-place Detroit Lions dropped to 1-4, after losing 28-20 at home to Pittsburgh.
Second-place Chicago and the third-place Packers had their byes Sunday.
The Bears are a game-and-a-half out of first, at 3-1. The Packers are at 2-2, and will host the Lions next Sunday.
Adrian Peterson scored twice on the ground for the Vikings, and he had 69 yards on 15 carries.
Brett Favre, who turned 40 on Saturday, threw for 232 yards, one touchdown, and an interception as the Vikes handed the Rams their 15th straight loss dating back to last season.
Lions' quarterback Daunte Culpepper was sacked seven times by the Pittsburgh defense.
He threw for 282 yards, a touchdown, and an interception in place of injured rookie Matthew Stafford.
Detroit receiver Calvin Johnson left in the first quarter with a right leg injury.
Ben Roethlisberger had three touchdown passes for the Steelers.