Justin Forsett and Marcus O'Keith also scored on the ground for the Golden Bears (2-1), who have won two in a row since dropping their opener to Tennessee.
Rob Freeman was 12-of-17 for 119 yards with a touchdown for Portland State (2-1), which was coming off a 45-3 victory over Northern Colorado. Tremayne Kirkland threw one touchdown pass and caught another in defeat.
The Golden Bears had 21 straight points in the first quarter, starting with a three-yard TD pass from Longshore to Cameron Morrah that capped a six-play, 55-yard drive.
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