Owusu, who was also hit hard last weekend in No. 4 Stanford's triple-overtime victory over USC, was prone on the field for several minutes after the hit midway through the second quarter.
He gave a thumbs-up after he was loaded on to a stretcher and placed into the ambulance. Details about his condition were not immediately available.
Going into the game, the senior receiver had 33 catches for 370 yards and two touchdowns this season.
He had a 33-yard run against the Beavers in the first quarter.