CORVALLIS, Ore. (AP) -- Yvenson Bernard ran for 140 yards and a pair of touchdowns, then caught another score, and Oregon State defeated Arizona 31-16 on Saturday.
Sean Canfield completed 17 of 30 passes for 139 yards for the Beavers (3-3, 1-2 Pac-10), who built a big early lead but did not surrender it like they had in their previous two games.
Willie Tuitama, who went into the game ranked atop the Pac-10 with an average of 320 yards passing, completed 18 of 38 passes for 222 yards for Arizona (2-4, 1-2).
Tuitama was intercepted three times after throwing four interceptions through the first five games.
Arizona appeared to have mastered its spread offense -- dubbed Air Zona -- in a 48-20 victory over Washington State last weekend. Tuitama threw five scoring passes and the Wildcats collected 567 yards in total offense.
But Arizona struggled on the ground against Oregon State, rushing for just 9 yards. Arizona's scoring came on Jason Bondzio's three field goals and Antoine Cason's 60-yard interception return.
Oregon State was coming off a stunning 40-14 loss to UCLA, in which the Beavers disintegrated in the final quarter, giving up a 14-12 lead. The week before, the Beavers led 19-0 at Arizona State before losing 44-32.
Bernard ran 20 yards for a touchdown to give the Beavers the early lead. The Wildcats narrowed it on Bondzio's 42-yard field goal.
Gerard Lawson, who fumbled three consecutive kickoffs in the Beavers' loss to UCLA, set up Oregon State's next scoring drive with a 56-yard kickoff return. The series culminated with Bernard's 9-yard touchdown run.
The Beavers made it 21-3 when Joey LaRocque intercepted Tuitama and ran 49 yards for the touchdown. Alexis Serna added a 31-yard field goal for the Beavers before the end of the first quarter.
Canfield's 6-yard scoring pass to Bernard made it 31-3.
The Wildcats narrowed it to 31-10 with 25 seconds to go before the half when Cason intercepted Canfield and returned it for a score.
Bondzio added a 37-yard field goal in the third quarter, then a 32-yarder early in the fourth for the final margin.
Canfield was intercepted twice in the game and was replaced for a time by backup Lyle Moevao, who completed three of five passes for 25 yards.
The Beavers have won eight of the last nine against the Wildcats, including last season's 17-10 victory in Tucson. But two seasons ago, Tuitama made his first career start and torched Oregon State for 335 yards in a 29-27 win.