EUGENE, Ore. (AP) — It became clear that LaMichael James wasn't too badly hurt when he and Oregon teammate Kenjon Barner danced on the sidelines before the start of the fourth quarter.
The junior duo bopped to "Shout!" with the rest of the crowd at Autzen Stadium as the No. 9 Ducks cruised to a 49-21 victory over Oregon State in the Civil War rivalry game to clinch the Pac-12 North and a spot in the league's first championship game.
Earlier in the quarter, James — who ran for 142 yards and the game's first touchdown — left with an injured left elbow.
"It's good," he said, vigorously flexing his elbow after the game. "I could've played."
The demonstration was assurance that he'd be ready next Friday night when Oregon (10-2, 8-1 Pac-12) host UCLA with a chance to win a third straight conference title and a spot in the Rose Bowl.
Quarterback Darron Thomas, who threw for 305 yards and four touchdowns, said a victory in the Civil War was one of the goals Oregon set at the start of the season. The Ducks have won the last four in the 115-game history of the rivalry.
"This was a big game for the team and we wanted to win it for Eugene," Thomas said. "The win wasn't just for us, it was for the fans."
The Beavers (3-9, 3-6) aren't going to a bowl game for the second straight season.
"I like this team for the fact that they kept working. It didn't amount to much today considering the result of the game, but I think the fact that they certainly have improved, they kept a good attitude," Oregon State coach Mike Riley said. "I think it's a tribute to the group of seniors that we have and I think it bodes well for the guys that are all coming back to this team when we get started in January. That's what we have to look forward to."
James, a Heisman finalist last season, entered the game as the nation's top rusher with an average of 142.78 yards per game. He was hurt midway through the third when he was hit by Oregon State linebacker Tony Wilson.
The junior running back was already wearing a brace on his right elbow, which he dislocated on Oct. 6 against California. He missed two games because of that injury.
Oregon looked as if it was making a strong bid for a spot in the BCS championship game until last weekend, when the Ducks fell to Southern California 38-35. But they tried bounced back easily against Oregon State.
Versatile freshman De'Anthony Thomas rushed for 71 yards and had 10 catches for 86 yards and a score. Barner ran for 64 yards and a touchdown, and also caught a scoring pass.
"I feel like we played real well," said De'Anthony Thomas, who finished with 197 all-purpose yards. "I can't wait to play next week. We're gonna play even better."
Redshirt freshman Sean Mannion threw for 299 yards and three touchdowns for the Beavers. But Oregon State struggled on the ground with just 16 yards rushing, compared to Oregon's 365.
James scored early on a 1-yard run, becoming Oregon's all-time leading scorer with 324 points.
The Beavers tied it at 7 when Jovan Stevenson grabbed a swing pass from Mannion and weaved his way downfield for a touchdown early in the second quarter.
"I don't know if I was nervous, more like excited," Mannion said. "You get to play in a rivalry and after the first play, it's just playing football. That's all there is to it."
Before the half Oregon scored on Darron Thomas' 16-yard pass to David Paulson and his 8-yard pass to De'Anthony Thomas.
Darron Thomas hit Barner with another 16-yard TD just before halftime to make it 28-7. Barner ran a yard for another score in the third quarter, and Thomas connected with freshman Colt Lyerla for a 39-yard touchdown early in the fourth.
Mannion threw two TDs in the fourth quarter to Kevin Cummings (19 yards) and Brandin Cooks (23 yards).
Oregon State flanker James Rodgers did not suit up because of a left ankle injury. It was to be the final game of a college career with some great moments and a severe injury.
In the 2007 Civil War, Rodgers scored on a fly sweep in overtime to give the Beavers a 38-31 victory at Autzen Stadium. Oregon State has not defeated their in-state rival since then.
"I told him I did not think he looked good and that I didn't think he should play," said Riley, who made the call after watching Rodgers in pregame warmups. "It's obviously tough, but ... being his last game also wouldn't have been any good to put him at risk. So I didn't think it was wise."
Rodgers was a fifth-year senior this season coming off a pair of knee surgeries.
Oregon linebacker Dewitt Stuckey (shoulder) and end Dion Jordan (ankle) both played against Oregon State after leaving with injuries against USC.
Last weekend's loss to USC at Autzen Stadium snapped a 21-game winning streak at home and a 19-game win streak in conference games. The Ducks haven't lost two straight at home since 2002.
"I felt like we shouldn't have lost that game," De'Anthony Thomas said. "But those things happen. Now we gotta get back and win the Pac-12 championship."