Published: Sep 02, 2012 2:23 AM EDT
Updated: Sep 02, 2012 6:32 AM EDT

EUGENE, Ore. (AP) - Marcus Mariota didn't show any signs of stage fright in his debut for the Ducks.

The redshirt freshman quarterback made his first start in a real game on Saturday night, passing for 200 yards and three touchdowns in No. 5 Oregon's 57-34 season-opening victory over Arkansas State.

De'Anthony Thomas caught two touchdowns and ran for another while collecting 119 yards in total offense as the Ducks built a 50-10 lead by halftime.

Kenjon Barner, taking over as starter after the departure of running back LaMichael James, ran for 66 yards and two scores.

The Ducks sat most of their starters after the break.

The loss spoiled coach Gus Malzahn's first game as coach of the Red Wolves, who went 10-3 last season and won the Sun Belt Conference title.