The Vikings defeated the 49ers on Sunday in large part by forcing three fourth-quarter turnovers that can best be described as unexpected:

1 Frank Gore fumbled at midfield, with Marvin Mitchell recovering, on the first 49ers' first offensive snap of the final quarter with the Vikings leading 24-13. It was Gore's first lost fumble since Week 5 of the 2011 season.

2 Quarterback Alex Smith had a 49ers' franchise-record 249 consecutive passes without an interception stopped with 2:18 to play when he was picked off by Josh Robinson.

3 Turnover No. 3 was a Smith fumble -- Brian Robison recovery -- with 1:33 left after being sacked by Jared Allen. Rare? The 49ers had gone 30 regular-season quarters without an offensive turnover, dating to Thanksgiving 2011.