The Colorado Buffaloes' bid to upset the No. 21 Arizona St. Sun Devils is off to a rough start as the Buffaloes have fallen to a deep deficit at halftime.

Arizona soared to an early lead, scoring touchdowns on two Brock Osweiler passes and a 19 yard Cameron Marshall run. With a 24-0 lead in the second quarter, the Arizona offense finally faltered as Josh Moten gathered in a Osweiler fumble, scoring on a 16 yard scoop-n-score special.

With Colorado finally on the board, Cameron Marshall pushed the lead to 31-7 with an 11-yard dash to the end-zone.

The Buffaloes offense has struggled through the first half with quarterback Tyler Hansen completing 13 of 21 for 160 yards and an interception. Meanwhile, running back Tony Jones has hit a bit of a wall, running for only 17 yards on 5 carries.

Colorado figures to pass the ball heavily going into the second half, looking for a comeback.

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