Oregon State's Markus Wheaton (2) celebrates a touchdown against California with quarterback Sean Mannion (4) and Kevin Cummings (84) during the first half of Saturday's game in Corvallis. Oregon State is a 10-point underdog against Oregon in Saturday's Civil War.

CORVALLIS — While they are still underdogs, the Oregon State Beavers certainly have reasons to be hopeful heading into Saturday’s football Civil War against rival Oregon.

The surprising No. 16 Beavers are not only buoyed by their own dramatic turnaround this season but also by the vulnerabilities No. 5 Oregon showed in last weekend’s loss to Stanford.

Oregon State has already defied the odds by improving to 8-2 overall after going just 3-9 last season. After two years without a bowl game, the Beavers were bowl eligible early after a 6-0 start, their best since the 1907 season.

They have also overcome an injury to starting quarterback Sean Mannion, and now one to successful backup-turned-starter Cody Vaz.

It all gives Oregon State more reason to be hopeful this season against Oregon, after four straight losses in the series. While Oregon State coach Mike Riley often says that in the Civil War “anything can happen,” the past two meetings were pretty much foregone conclusions.

Last season, the then-No. 9 Ducks beat the Beavers 49-21 in Eugene, clinching the Pac-12 North’s spot in the inaugural Pac-12 Conference championship game. The Ducks would go on to defeat UCLA for the league title before a 45-38 victory over Wisconsin for their first Rose Bowl win in 95 years.

The season before, Oregon beat Oregon State 37-20 in Corvallis. That win sent the Ducks on to the BCS championship game against Auburn, while the loss kept the Beavers from becoming bowl eligible.

Oregon State has not won the Civil War since an overtime upset at Autzen Stadium in 2007.

“It’s great to be where we are,” Riley said. “We try not to be surprised by success, we work for that hard. But I am proud of the turnaround in this team and the work they did in the offseason and what they’ve accomplished to this point. It’s much more fun and exciting to be going into the Civil War at 8-2 rather than 3-8, or whatever we were.”

Oregon (10-1, 7-1) is wounded heading into the 116th edition of the rivalry game after a 17-14 overtime loss to Stanford last Saturday at Autzen Stadium.

The loss knocked Oregon out of the top spot in the AP rankings and complicated the Ducks’ bid for a second national championship game berth in three seasons.

Oregon would have clinched the Pac-12 North for the second straight season with a victory against the Cardinal. Instead, the Ducks will have to wait a week to see how the conference shakes out.

If No. 11 Stanford (9-2, 7-1) can defeat No. 15 UCLA (9-2, 6-2) on Saturday at the Rose Bowl, the Cardinal will go to the conference championship. If Stanford loses and Oregon wins, the Ducks will go to the Pac-12 title game.

The winner of the conference title game gets a Rose Bowl berth — unless the winner is tapped for a place in the national championship. The Bruins have already clinched the Pac-12 South.

Oregon is not out of the mix for the BCS title game just yet, but it will need USC (7-4, 5-4) to defeat top-ranked and undefeated Notre Dame on Saturday. That is a tall order for the Trojans, who have lost three of their past four games and will not have senior quarterback Matt Barkley. Freshman Max Wittek will make his first career start in place of Barkley, who hurt his right shoulder in last weekend’s 38-28 loss to UCLA.

“There’s a lot of disappointment, but it’s one game,” Oregon quarterback Marcus Mariota said in the wake of the Stanford loss. “The season’s not over. We have a lot to play for.”

He is right. Even if the Ducks do not play in the conference championship, they could be an at-large selection for one of the other BCS bowls, a scenario that seems likely if they defeat Oregon State and finish the season with just one loss.

Interestingly, Oregon State’s season is also far from over. Win or lose to the Ducks, the Beavers have a home game set for Dec. 1 against Nicholls State. (The Beavers were supposed to open the season on Sept. 1 against the Colonels, but the game was postponed because of the threat Hurricane Isaac posed to the school’s Thibodeaux, La., campus.) Then Oregon State will await its bowl bid.

Riley announced on Monday that Mannion would start Saturday at Reser Stadium. Mannion started the first four games of the season, throwing seven touchdown passes and averaging 339 yards, but he injured his left knee and required surgery. Vaz, who had not started since high school, took over and helped the Beavers to win in the next two games, and he later became the team’s starter.

But Vaz sprained his left ankle in the final moments of a loss at Stanford, and he sat out last Saturday during Oregon State’s 64-14 victory at home over California.

As of Tuesday, Oregon was about a 10-point favorite over Oregon State.

Stanford coach David Shaw, who has defeated both Oregon and Oregon State this season, was asked on Tuesday for his assessment of Saturday’s matchup in Corvallis.

“Whatever defense can keep the offense from making the big plays will have a good chance to win,” he said.