Jeremiah Johnson bobbles the on the way to an 83-yard touchdown run as Oregon State’s Al Afalava (9) and Austin Hall miss a tackle late in the first half Saturday. Associated Press Photo.

CORVALLIS — Oregon State University head football coach Mike Riley, ever an optimist, wearing his typical relaxed smile, looked out to a group of reporters Saturday evening and said the obvious.

“Oregon played better than the Beavers tonight — that’s the bottom line,” Riley said.

What the orange-clad OSU crowd expected to be a big celebration for Oregon State honoring the team’s return to the Rose Bowl for the first time in 45 years instead turned into a party for the Ducks and their fans at Reser Stadium.

The final score was stunning — 65 to 38 Oregon.

Facing their biggest game in years, the Beavers fell flat, their defense unable to stop Oregon’s spread-option attack.

The post-game emotions were understandable.

“It hurts, it definitely hurts — going on a long stretch like this and not being able to top it off,” said Oregon State quarterback Lyle Moevao.

Meanwhile, the Ducks enjoyed spoiling Oregon State’s party, just as the Beavers had done to Oregon in the same stadium in 2000 when Oregon had a chance to clinch a Rose Bowl berth.

Oregon quarterback Jeremiah Masoli said the team’s goal wasn’t necessarily ruining Oregon State’s dreams.

“We were just trying to come out and execute our game plan, and we did,” he said.

The tone of the game was established early.

The Beavers quickly stopped Oregon’s first drive, but couldn’t take advantage of great field position.

On the Ducks’ next drive, Oregon State’s Brandon Hughes dropped a ball Masoli threw right to him and Oregon had a touchdown two plays later.

The Ducks added a field goal by Morgan Flint on their next possession, and the Beavers responded with their first touchdown.

Oregon was pinned on its own 12 after the kickoff, but then had the first of several huge plays in the game — a 79-yard run by Jeremiah Johnson that set up a touchdown by LeGarrette Blount.

The Beavers drove to Oregon’s 6-yard line, but the drive stalled and Justin Kahut missed a 21-yard field goal attempt.

Flint kicked another field goal and the Beavers moved inside Oregon’s 10 again, but couldn’t find the end zone. Kahut made a field goal, but Riley said the missed opportunity was huge.

“We were down twice inside the 10 and came away with three points,” he said. “That was a major factor early.”

The other major factor, throughout the game, was big plays.

Oregon State’s defense came in ranked second in the conference, but looked terrible, giving up nearly 700 yards of total offense.

The Ducks had eight plays go for at least 35 yards in the game.

Arguably the biggest came with a minute to go in the first half, when Oregon faced third-and-19 and Johnson broke loose for an 83-yard touchdown run, breaking several weak tackle attempts along the way.

Walter Thurmond III intercepted a pass by Moevao on the next offensive play and returned it 40 yards for a score and the Ducks suddenly had a 37-10 lead.

The Beavers scored before halftime and cut the lead to 13 early in the third quarter, but couldn’t stop the big plays.

Blount had a 46-yard run to help set up a touchdown run by Masoli that put the Ducks up by 20 again.

The Beavers countered with another touchdown, but Masoli hit Terrence Scott for a 76-yard score on a third-and-seven play.

Oregon State cut the lead to 13 one more time with 8:34 to go in the game, but Masoli hit tight end Ed Dickson for a 45-yard score on another third-down play. Spencer Paysinger’s 70-yard interception return was the final dagger.

After the game, Masoli said the offensive explosion was critical on Oregon State’s home turf.

“Tonight was crazy,” he said. “The fans were crazy. We did our best to keep them quiet.”

Oregon benefited from having a bye week before the game, which gave the Ducks lots of time to prepare for Oregon State’s fly sweep, a critical play given the absence of the Pac-10’s leading rusher, Jacquizz Rodgers.

Oregon also was helped by his injury.

Rodgers is a shifty back who creates a lot of extra yards by making quick moves and breaking tackles. Ryan McCants, who started in his place, rarely broke a tackle. His best run of the night ended in a fumble that turned into one of three turnovers to the Ducks.

Moevao was asked how Rodgers would have impacted the game.

“It would have been a lot different,” he said.

But Rodgers couldn’t have helped the defense, which was Oregon State’s biggest problem area.

“We had a good game plan,” said defensive lineman Slade Norris. “The coaches did a good job preparing us. The responsibility goes to the players. We didn’t execute.”

With the win, Oregon probably secured a berth in the Holiday Bowl, which goes to the second-place team in the Pac-10. The Ducks and Beavers ended the year tied at 7-2 in league play, but Oregon has a better overall record at 9-3, to go with the Civil War win.

Technically, the Beavers still have a chance to go to the Rose Bowl, if UCLA can beat USC this week and force a three-way tie atop the Pac-10 between the Trojans, Ducks and Beavers. Riley was asked about that possibility, unlikely as it might be.

“I’m not going to lose any sleep over that one,” Riley said. “The biggest thing is to get this team feeling good again.”

That, he said, will take time.

“We’ve been on a six-week playoff run and (the bubble) burst tonight,” Riley said.