Trevor Siemian went 18-of-29 through the air for 276 yards with a touchdown while overcoming two interceptions as the Wildcats (1-0) won their season opener after downing Mississippi State in last year's Gator Bowl -- the program's first post-season win since 1949.
Treyvon Green led Northwestern's ground game with 129 yards on 16 carries, while Dan Vitale paced the receiving corps with five grabs for 101 yards.
The Golden Bears (0-1) were led by freshman quarterback Jared Goff, who completed 38-of-63 passes for 445 yards, two touchdowns and three interceptions.
Chris Harper hauled down 11 passes for 151 yards and two scores for Cal.
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