Mariota compiled 321 yards of total offense, completing 14-of-28 pass attempts for 199 yards while carrying the ball four times for 122 rushing yards in the victory.
De'Anthony Thomas led the ground game for the Ducks (2-0), scoring three times on 11 carries en route to 124 yards, while freshman Thomas Tyner chipped in two TDs runs on his way to 51 yards on four attempts.
The Cavaliers (1-1) were hampered by three interceptions and a lost fumble by David Watford, who completed 29-of-41 passes for 161 yards.
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